Direct answer
For the Samsung Galaxy S24, one app versus the operating system, storage and service state determines the safe sequence. First, force close and restart the device, then check app/system updates and free space.
What this covers
- Samsung Galaxy S24 (SM-S921*)
- Samsung Galaxy family; S Pen, foldable display, DeX, USB moisture and One UI features vary by exact model.
- The specific fault this record addresses: app keeps crashing, freezing or will not open
What it does not cover
- ×The same symptom on a different Samsung product line, which has its own record and its own cited source
- ×An on-screen error code whose meaning has not been checked against this exact model's manual
- ×Live electrical, gas, sealed-system, internal battery-cell or structural repair — a technician boundary, not a self-service step
Differential
What actually causes this, and how to tell them apart
These are ordered by how often each one is the answer, not by how easy it is to try. The point of the middle column is that two causes producing the same headline symptom rarely produce the same detail — that detail is what tells you which one you have before you change anything.
- 1
The app's stored data has become corrupt
What separates it It crashes immediately on launch, every time, having worked before. Cache and stored state can be left inconsistent by an interrupted update or a full disk.
How to confirm Clear the app's cache first, then its data if that fails. Clearing data signs you out and discards local content, so it is the second step, not the first.
- 2
Storage is full or nearly full
What separates it Several apps misbehave at once, updates fail, and the camera refuses to save. An app that cannot write cannot run reliably.
How to confirm Check free storage before anything app-specific. Below a few percent free, all bets are off across the whole phone.
- 3
The app version and the OS version disagree
What separates it It broke immediately after an OS update, or after an app update on an older OS. Compatibility runs both ways.
How to confirm Check for an app update, and check whether the app still supports your OS version. An app that has dropped support for your OS will not be fixed by reinstalling it.
- 4
A permission it needs was revoked
What separates it It crashes at one specific action — opening the camera, attaching a file, starting a call. An app given a hard denial where it expected access can fail rather than degrade.
How to confirm Check the permissions for that app against what the failing action needs.
- 5
A specific piece of content is triggering it
What separates it It crashes on one conversation, one photo, one file, and is fine otherwise. A malformed item can take the app down every time it is rendered.
How to confirm Note exactly what was on screen or being opened. A reproducible trigger is a report worth sending to the developer, and it is also avoidable in the meantime.
- 6
The phone is out of memory
What separates it Apps close in the background and have to reload constantly, worse with many apps open or during heavy use. This presents as apps 'restarting' rather than crashing.
How to confirm Restart the phone and compare. Reloading rather than crashing is a memory symptom, not an app fault.
- 7
A bad update from the developer
What separates it It started for many people on the same date, and the app store reviews say so. Nothing on your phone caused it.
How to confirm Check recent reviews and the developer's status channels before spending time on your own configuration.
- 8
An account or sign-in state that cannot be resolved
What separates it It crashes at the sign-in step or immediately after. A stale token can put the app into a state it cannot recover from.
How to confirm Sign out and back in where possible before clearing data, since signing out is the lesser action.
- 9
Overheating
What separates it Crashes cluster during heavy use or in the sun, and stop when the phone cools. A throttling phone changes performance underneath the app.
How to confirm Let it cool and retry the same action.
Before you touch a setting
Record this first — changing settings destroys the evidence
Every item below stops existing the moment a reset, re-pair or settings change is made. Written down first, they are what separates the causes above; recovered afterwards, they are guesswork.
- Whether it crashes on launch, at a specific action, or randomly during use. Those are three different faults.
- Whether one app is affected or several, which separates an app problem from a phone problem.
- The date it started, and what happened then: an OS update, an app update, a full disk, a new account.
- Exactly what was on screen or being opened when it failed, since a reproducible trigger is the most valuable single fact.
- Free storage on the phone.
- The app version and the OS version.
- Whether the phone was hot at the time.
Establish the pattern before changing anything
ReversibleCrashing on launch, at one specific action, or randomly are three different faults with three different fixes. Reinstalling first destroys the evidence that would have told you which one you had.
Check free storage
ReversibleAn app that cannot write cannot run reliably, and below a few percent free the whole phone misbehaves — several apps at once, failed updates, a camera that will not save. This is a phone-level cause that looks like an app-level one.
Restart the phone
ReversibleApps that reload constantly rather than crashing outright are describing memory pressure, not a defect. A restart clears it, and comparing before and after distinguishes the two in a couple of minutes.
Check for an app update and an OS compatibility gap
ReversibleCompatibility runs both ways: an OS update can break an old app, and an app update can drop support for an old OS. An app that no longer supports your OS version will not be fixed by reinstalling it, which is where a lot of effort gets wasted.
Check the permissions the failing action needs
ReversibleAn app crashing at one specific action — opening the camera, attaching a file, starting a call — is frequently one that was given a hard denial where it expected access and did not handle it gracefully.
Clear the cache before clearing data
Signs you outCache is disposable; data is your local content and your session. Clearing cache costs nothing and fixes a real share of corrupt-state crashes. Clearing data signs you out and discards what is stored locally, which is why it comes second.
Check the app store reviews and the developer's status
ReversibleA crash that started for many people on the same date is a bad release, and nothing on your phone caused it or will fix it. Thirty seconds of reading prevents an afternoon of configuration.
Note the exact trigger where one exists
ReversibleOne conversation, one photo, one file that reliably takes the app down is the most valuable fact available — it is a report the developer can act on, and it is avoidable in the meantime.
Reinstall last, and know what it costs
Signs you outIt clears everything local and re-prompts for permissions, which is why it sometimes works. It also discards anything not synced, and it teaches you nothing about the cause — so it belongs after the cheaper, more specific steps.
Model-specific
What is true of this model and not of its siblings
Generic advice for the product line fails here. Each item below is a property of this specific model family that changes which of the steps above apply to you.
- Model scope
- SM-S921*. Samsung Galaxy family; S Pen, foldable display, DeX, USB moisture and One UI features vary by exact model.
- Display
- 156.4mm (6.2" full rectangle) / 152.3mm (6.0" rounded corners), 2340 x 1080 (FHD+), Dynamic AMOLED 2X, up to 120 Hz. Samsung quotes two figures for screen size — the full rectangle and the rounded-corner measurement — which is why this phone is listed at two different sizes in different places and neither is wrong.
- Refresh rate
- Up to 120 Hz adaptive. A high refresh rate is one of the larger discretionary battery costs on this phone: it is genuinely smoother and it genuinely costs runtime, which is why battery complaints on this model are worth checking against the refresh-rate setting before anything else.
- Panel
- Dynamic AMOLED 2X. This is an AMOLED panel, so dark mode reduces consumption for real — black pixels are switched off rather than backlit — and a static bright element left on screen for very long periods is the one wear risk this panel type has.
- Rear cameras
- 50.0 MP + 10.0 MP + 12.0 MP. The main sensor is 50 megapixels, which produces substantially larger files than a 12-megapixel camera and is a meaningful contributor to how quickly storage fills.
- Zoom
- Optical Zoom 3x, Optical quality Zoom 2x (Enabled by Adaptive Pixel sensor). Zoom range is the practical difference between models in this line. A close-up that will not focus at the long end is normally the telephoto's minimum focus distance rather than a fault — taking the same shot at 1x confirms it in seconds.
- Video
- UHD 8K (7680 x 4320)@30fps. Resolution and frame rate dominate how quickly video fills storage and how hard the phone works thermally — sustained 8K recording is the single most common reason a Galaxy camera stops mid-take and warns about temperature.
- Memory and storage
- 8GB RAM with a 128GB storage tier. RAM matters directly to one symptom: apps reloading when you switch back to them is memory pressure rather than a crash, and it is more likely on the lower-RAM configurations.
- SIM
- SIM 1 + SIM 2 / SIM 1 + eSIM / Dual eSIM. Three combinations are supported, and the default line for calls, for messages and for cellular data are three separate settings — crossing them produces calls arriving on one number while data or messages use another, with almost no indication that anything is wrong.
- Wi-Fi
- 802.11a/b/g/n/ac/ax 2.4GHz+5GHz+6GHz, HE160, MIMO, 1024-QAM. This is Wi-Fi 6E hardware with 6 GHz support. A router running a newer standard falls back rather than refusing, so a difference against a newer phone on the same network is specification rather than fault.
- Bluetooth
- Bluetooth v5.3. Version affects range, reconnection behaviour and which accessory features are available — a newer accessory paired here operates at this version's capabilities rather than failing, which is regularly mistaken for a pairing fault.
- Connector
- USB Type-C. Note that a USB-C cable which fits is not necessarily rated for this phone's charging speed: USB-C carries several power profiles, and a data-oriented cable charges slowly or intermittently while seating perfectly.
- Processor
- 3.2GHz, 2.9GHz, 2.6GHz, 1.95GHz. Clock speed is not the useful number for troubleshooting; what matters is that sustained heavy work throttles, so performance measured while the phone is already hot is measuring the throttling rather than the phone.
- Samsung's own specification
- Samsung publishes the full specification for this model at samsung.com/uk/smartphones/galaxy-s24/specs/. Where any figure above matters to a decision, that page is the authority and this one is not.
- Biometric
- An in-display fingerprint reader, which looks through the screen. A thick or incompatible screen protector genuinely interferes with it, which is why unlock reliability often changes the day a protector is fitted rather than gradually.
- Modem
- 5G capable. In marginal 5G coverage the phone hands repeatedly between 5G and LTE, which costs more battery and generates more heat than settling on either — so the preferred-network setting is a real diagnostic lever rather than a preference.
- Charging
- Supports wireless charging. Coil alignment is tighter than it looks and a thick case, a metal plate or a card in the case defeats it entirely — so wireless charging failing while cable charging works is usually the case rather than the phone.
- Water resistance
- Rated water resistant, which is not waterproof and which degrades with age, drops and seal disturbance. The rating covers incidental exposure; it is not a guarantee, and moisture-detection warnings are deliberately conservative and can persist after the port feels dry.
- Platform
- Android, with a manufacturer interface layer over it. Battery optimisation and background-execution restrictions are applied per app and are far more aggressive than on iOS — which is why 'set this app to unrestricted' is a real fix here and has no equivalent elsewhere.
- Symptom boundary
- This record covers Samsung Galaxy S24 when it app keeps crashing, freezing or will not open. A different symptom on the same hardware, or this symptom on a different Samsung product line, has its own record with its own causes and its own cited source.
Stop boundary
When this stops being a self-service repair
Continuing past any one of these costs more than the repair saves — in safety, in warranty, or in evidence a technician needs.
- !Several unrelated apps crash after every step here, which points at the phone rather than any app.
- !The app has dropped support for your OS version — no reinstall changes that, and the choice is the OS or the app.
- !A reproducible crash on specific content, which is a developer matter and worth reporting with the exact trigger.
- !The phone restarts itself rather than the app closing, which is a system-level fault.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Where the manufacturer's article stops. Samsung publishes this as "App is crashing or not working on Samsung phone or tablet". Covers apps that crash, freeze or will not open on a Galaxy phone - force stop, clear cache, update and safe mode. Probed 2026-08-21: title-verified. What that article does not carry is the model boundary — it is written for a product line, and SM-S921* is the scope applied here. Where a control label, terminal, indicator pattern or reset sequence differs on your unit, the manual for that exact model is the authority, not this page and not the article.
Exact questions
Common follow-ups
What size is the Galaxy S24 screen?+
Samsung lists 156.4mm (6.2" full rectangle) / 152.3mm (6.0" rounded corners), at 2340 x 1080 (FHD+). The two size figures are the full rectangle and the rounded-corner measurement — both are Samsung's own numbers, which is why this phone appears at two different sizes in different places.
Does the Galaxy S24 have a 120Hz screen?+
Yes, up to 120 Hz adaptive on a Dynamic AMOLED 2X panel. It is worth knowing for battery complaints specifically: a high refresh rate is one of the larger discretionary costs on this phone, and it is the first setting to check when runtime is disappointing.
Does dark mode save battery on the Galaxy S24?+
Yes, genuinely — it uses an Dynamic AMOLED 2X panel, where black pixels are switched off rather than backlit. The saving is real though smaller than reducing brightness or refresh rate, which remain the larger levers.
What cameras does the Galaxy S24 have?+
50.0 MP + 10.0 MP + 12.0 MP, with optical zoom 3x, optical quality zoom 2x (enabled by adaptive pixel sensor).
How much storage and RAM does the Galaxy S24 have?+
8GB RAM and a 128GB storage tier. The RAM figure is the one that matters for a specific symptom: apps reloading from scratch when you switch back to them is memory pressure rather than crashing, and it is more likely on lower-RAM configurations.
Does the Galaxy S24 support eSIM?+
Yes — Samsung lists SIM 1 + SIM 2 / SIM 1 + eSIM / Dual eSIM. Because more than one line can be active, check which line is set as the default for calls, for messages and for cellular data separately; those are three settings and crossing them is easy to do and hard to notice.
What Wi-Fi does the Galaxy S24 support?+
802.11a/b/g/n/ac/ax 2.4GHz+5GHz+6GHz, HE160, MIMO, 1024-QAM. That is Wi-Fi 6E with 6 GHz support; a router on a newer standard falls back rather than refusing, so a gap against a newer phone is specification rather than a fault.
Can the Galaxy S24 record 8K video?+
Yes — UHD 8K (7680 x 4320)@30fps. Bear in mind that resolution and frame rate dominate both how fast storage fills and how hard the phone works thermally, and sustained 8K is the most common reason a Galaxy camera stops mid-recording with a temperature warning.
What Bluetooth version is the Galaxy S24?+
Bluetooth v5.3. Version affects range, reconnection and which accessory features are available — a newer accessory paired here runs at this version's capabilities rather than failing, which regularly gets misread as a pairing fault.
One app crashes every time I open it.+
Clear its cache first — corrupt stored state after an interrupted update or a full disk is a common cause and cache is disposable. Clear its data only if that fails, because data means your session and your local content.
Several apps started crashing at once.+
Check free storage first. Below a few percent free the whole phone misbehaves — apps crash, updates fail, the camera will not save. It looks like several app faults and it is one phone-level cause.
It broke right after a system update.+
Check for an app update, and check whether the app still supports your OS version. Compatibility runs both ways, and an app that has dropped support for your OS will not be fixed by reinstalling it — which is where most of the wasted effort on this goes.
Should I just reinstall it?+
Last, not first. A reinstall clears local data and re-prompts for permissions, which is why it sometimes works, but it discards anything unsynced and teaches you nothing about the cause. Cache, storage, permissions and a restart are all cheaper and more specific.
Apps keep reloading when I switch back to them.+
That is memory pressure rather than crashing. The phone is closing background apps to make room, and they reload from scratch when you return. A restart clears it; if it recurs constantly, having fewer heavy apps open is the practical answer.
It crashes on one particular chat or photo.+
That is the most useful thing you could have found. A reproducible trigger is a report the developer can act on, and it is avoidable meanwhile. Note exactly what was on screen — that detail is the whole value of the report.
It crashes when I try to attach a photo.+
Check its permissions. An app crashing at one specific action is frequently one that was given a hard denial where it expected access and did not handle the refusal gracefully. The action names the permission to look at.
Everyone I know has the same problem with this app.+
Then it is a bad release and nothing on your phone caused it. Check the app store reviews and the developer's status channels — waiting for the next version is genuinely the correct action, and reinstalling only reinstalls the broken version.
It only crashes when the phone is hot.+
A throttling phone changes performance underneath the app, and some apps do not handle that well. Let it cool and repeat the same action — crashes that cluster during heavy use or in the sun and stop when cool are thermal rather than defects.
Does this answer apply to every Samsung model?+
No. It is scoped to SM-S921*. Samsung Galaxy family; S Pen, foldable display, DeX, USB moisture and One UI features vary by exact model.
What should I record before troubleshooting app crashing or freezing?+
Record the complete model identifier, exact message or indicator, software/firmware where visible, the operating stage and what still works.
Why is a factory reset not the first step?+
A reset can erase accounts, networks, maps, schedules or preferences without distinguishing app crashing, freezing. The ordered checks preserve that evidence.
When should I stop and use qualified service?+
Do not delete the only authenticator, banking or unsynced-data app without recovery access.
Answer for the exact device and software version shown above.