Quick answer: the six faults that show up on our bench week in, week out are a cracked or unresponsive screen (still the number one job — roughly six in ten repairs start here), a battery that drains fast or has visibly swollen, a blurry or cracked camera lens, a charging port that's loose or won't hold a cable, a speaker or microphone that's gone quiet or crackly, and water damage after a drop in the sink, toilet or rain. Screens and batteries alone account for the majority of what independent repair shops see across both iPhone and Samsung ranges, and most of them are straightforward DIY jobs with the right part and 20–40 minutes on a clean desk. Below we go fault by fault: what's actually causing it, whether it's realistic to fix yourself, what part you need, what it costs, and when to stop and hand it to a professional instead.
Why is my iPhone or Samsung screen cracked or unresponsive?
Screens fail in two distinct ways and it matters which one you've got. A cracked screen is physical — you dropped the phone, the glass took the impact, and now there's a spiderweb across the display or a chip in the corner. A digitiser fault is different: the glass looks fine but touch input has gone dead in patches, ghost-touches by itself, or doesn't respond at all. Digitiser faults after a drop are usually the flex cable connector shaking loose inside the phone rather than the glass itself being the problem, though a hard enough impact cracks the LCD or OLED panel underneath and takes touch response with it.
Is this DIY? Genuinely, yes, for most models — screen replacement is the most standardised repair in the trade and every iPhone from the X onwards uses Face ID components that need transferring across (earpiece speaker, sensor cluster) rather than swapping wholesale, which is the one part people trip up on. Samsung flagships with curved edges (S-series Ultra and Plus models) are fiddlier because of the curved glass bonding, but still doable with patience, a heat mat and the right adhesive.
Budget iPhone LCD screens run from around £19–£25 for iPhone 13/14/15 generation panels; OLED on the current iPhone 16 range sits at £140 because Apple's Face ID calibration and True Tone hardware make the part itself expensive, not the labour. Samsung Galaxy S-series OLED with the frame pre-fitted (which saves you having to transfer the frame yourself) runs roughly £70–£120 depending on model.
Buy Now → iPhone 13 FHD LCD Screen, £18.98 Buy Now → iPhone 16 OLED Screen, £139.98 Buy Now → Galaxy S22 Ultra OLED Screen with Frame, £79.98
Don't forget the consumables — pre-cut screen adhesive and a set of opening tools make the difference between a clean job and a phone that rattles or lets dust in afterwards.
Buy Now → iPhone XR Screen Assembly Adhesive, £0.99 Buy Now → 10-in-1 Repair Tool Kit, £0.99
Take it to a pro if: the crack has spread under the frame edge and the chassis itself is bent, or if touch is dead and the phone shows other damage (bulging back, no Face ID) — that's usually a sign the logic board took a knock too, and a screen swap alone won't fix it.
Why does my phone's battery drain fast or look swollen?
Lithium-ion cells degrade with every charge cycle — that's physics, not a fault — but a battery that's dropped noticeably below its rated capacity, that a phone reports as "service recommended" (iPhone) or that visibly bulges the back cover or screen upward (Samsung and iPhone both) needs replacing, not charging around. A swollen battery is not cosmetic. It's a chemical breakdown inside the cell and it's a genuine fire risk if you keep using or charging it — stop, and don't puncture or bend the cell when you remove it.
Is this DIY? Battery swaps are one of the highest-volume jobs in the trade — independent shops report battery work makes up a meaningful chunk of their repair revenue on its own, second only to screens. On most Samsung Galaxy A-series phones the battery is a straightforward pull-and-replace behind the back cover, genuinely a 15-minute job. iPhones are trickier because Apple bonds the cell in with adhesive pull-tabs rather than a removable tray — go slowly, never lever with metal near the cell, and if a pull-tab snaps, stop and use isopropyl alcohol to soften the adhesive rather than prying harder.
Realistic cost: Samsung A-series cells run roughly £8–£10 for the battery itself. iPhone battery jobs need fresh adhesive strips every time (reusing old adhesive is how you end up with a loose battery rattling inside the case) — budget £2 for strips on top of whatever cell you're fitting, and if the back glass has already been pushed up by swelling, budget for a replacement back cover too.
Buy Now → Samsung Galaxy A12 5000mAh Battery, £8.99 Buy Now → Samsung Galaxy A03s 5000mAh Battery, £9.99 Buy Now → iPhone Battery Adhesive Strips, £1.99 Buy Now → iPhone 14 Pro Max Battery Back Cover, £12.99
Take it to a pro if: the swelling is severe enough that the screen or back glass has visibly lifted and separated — at that point the cell is unstable and needs careful, controlled removal, not a DIY pry session at the kitchen table.
Why is my camera blurry, or the lens cracked?
Two separate problems get lumped together here. A cracked or scratched lens cover — that little glass disc over the camera housing — causes light scatter and hazy, flared photos even though the camera module underneath is perfectly healthy. A genuinely blurry or non-focusing camera, where photos are soft even in good light or the camera app won't focus at all, means the module itself (or its flex cable) has failed, often after a drop that jolted the autofocus motor or from moisture ingress fogging the internal element.
Is this DIY? Lens-only replacement is one of the easiest and cheapest fixes on this whole list — it's a small glass disc bonded with adhesive, no ribbon cables involved on most models, and parts run under £2. Swapping the full camera module is more involved, particularly on iPhone Pro models where the rear module is calibrated to the logic board and Apple's software will flag an "unable to verify" warning after a non-genuine swap (it still works, but you'll see the notification).
Buy Now → iPhone 13 Pro/Pro Max Camera Lens Glass, £1.99 Buy Now → iPhone 12 Pro Rear Camera Module, £110.99 Buy Now → Samsung Galaxy A22 5G Main Camera, £9.99 Buy Now → Samsung Galaxy A12 Rear Camera Lens with Adhesive, £1.99
Take it to a pro if: you need a full Pro-series camera module swap and want to avoid the calibration warning, or if the fault only appeared after water exposure — check for moisture under the lens first (a foggy ring is the giveaway) before spending on a new module.
Why won't my phone charge, or the port feels loose?
A charging port fault has three usual suspects, in order of likelihood: pocket lint and dust packed into the port (genuinely the most common cause — try a wooden toothpick and a torch before buying anything), a bent or worn contact pin inside the port from repeated cable insertion at an angle, or a cracked solder joint on the small flex board the port sits on, usually from the phone being dropped port-first or the cable being yanked sideways. If the phone charges fine sitting dead still but cuts out the moment you nudge it, that's a loose connector, not a dead battery or a bad cable.
Is this DIY? Yes on both platforms, and it's one of the more satisfying fixes because it's usually a single flex cable held by two or three screws and a connector, no adhesive to fight. iPhone charging port flex assemblies often bundle the main microphone on the same flex (so a "can't charge" and "people can't hear me on calls" complaint sometimes have the same root cause and the same fix). Samsung's boards vary — some models bundle the headphone jack and mic too.
Buy Now → iPhone 12/12 Pro Charging Port Flex, £7.99 Buy Now → iPhone 11 Charging Port Flex with Microphone, £8.99 Buy Now → Samsung Galaxy A52 Charging Port Board, £11.99 Buy Now → Samsung Galaxy A22 5G Charging Port with PCB Board, £3.99
Take it to a pro if: cleaning the port and swapping the flex both fail to fix it — at that point the fault has likely migrated to the main board itself (a blown charging IC), which needs microsoldering, not a parts swap.
Why can't I hear calls, or why has my mic gone quiet?
Split this into two components because the fixes and parts are different. The earpiece speaker (the small speaker you hold to your ear for calls) going crackly, quiet or silent is usually dust or ear grease built up over the mesh, or the speaker itself failing after a drop. The loudspeaker (bottom-firing, used for music, speakerphone and ringtones) rattling or distorting at volume is very often a symptom of a phone that's been dropped in water at some point, even briefly — the speaker mesh is one of the least sealed points on most phones.
Is this DIY? Both are simple flex-cable or clip-in component swaps, usually £2–£20 depending on model and whether the part is bundled with the proximity sensor (iPhone often pairs the earpiece with the Face ID sensor flex, which is why "genuine" replacement parts on iPhone can carry a serial-pairing warning in Settings — cosmetic, doesn't affect function).
Buy Now → iPhone 13 Loudspeaker, £5.49 Buy Now → iPhone 13 Earpiece Speaker, £9.99 Buy Now → Samsung Galaxy A22 5G Loud Speaker, £3.99 Buy Now → Samsung Galaxy A22 5G Earpiece Speaker, £1.99
Take it to a pro if: a new speaker doesn't fix it — that points to the audio IC on the main board, and no amount of speaker-swapping will solve a board-level fault.
My phone got wet — what now, and is it fixable?
Water damage is the fault most people panic-buy a new phone over, and the most misunderstood one on this list. What actually kills a wet phone is almost never the water itself — it's corrosion forming on the board over the following days as residual moisture reacts with the metal contacts, or a short circuit if the phone is powered on and charged while still wet inside. IP-rated iPhones and Samsung flagships resist splashes and brief submersion when the seals are intact, but that rating degrades over the phone's life as seals age, and a rating is void the moment the phone has been opened for any other repair.
Is this DIY, first steps: power off immediately, don't charge it, don't put it in rice (it does nothing useful and can get grains stuck in the ports), remove the SIM tray to let that channel drain, and leave it somewhere warm and dry for 48 hours minimum before attempting to switch on. If a specific function fails after drying — charging port, speaker, one camera — treat it as that individual fault and replace the affected part using the sections above, since parts corrode independently and a full water-damage board repair is rarely worth it on an older device.
Buy Now → iPhone 13 SIM Card Tray, £1.99 Buy Now → 10-in-1 Repair Tool Kit (for opening and drying), £0.99
Take it to a pro if: the phone won't power on at all after drying, or powers on but behaves erratically (random touches, backlight but no display, battery drains in minutes) — that's corrosion on the board itself, and it needs an ultrasonic clean and component-level inspection that isn't a home job.
Common faults at a glance
| Fault | Likely cause | DIY difficulty | Typical part cost (GBP) |
|---|---|---|---|
| Cracked / unresponsive screen | Impact damage or loose digitiser connector | Moderate | £19 (LCD) – £150 (flagship OLED) |
| Battery drains fast / swollen | Cell degradation past rated cycles | Easy (Samsung) / Moderate (iPhone adhesive) | £2 (adhesive) – £10 (cell) |
| Camera blurry / lens cracked | Scratched lens glass or failed module/motor | Easy (lens) / Moderate (full module) | £2 (lens) – £111 (module) |
| Charging port loose / not charging | Debris, bent pin, or cracked flex solder joint | Moderate | £4 – £18 |
| Speaker / mic quiet or crackly | Debris, drop damage, or minor water ingress | Easy | £2 – £15 |
| Water damage | Corrosion forming after moisture exposure | Hard (board-level) / Easy (single part swap) | Varies by affected part |
Frequently asked questions
Is it cheaper to repair my iPhone or Samsung myself, or pay a shop?
Doing it yourself is almost always cheaper on parts alone — you're paying £10–£150 for the component versus £50–£300 all-in at most independent shops once labour is added. The trade-off is time, the right tools, and a steady hand on fiddly jobs like flagship curved-glass screens.
Will replacing my screen or battery myself void my warranty?
If your phone is still under Apple or Samsung's manufacturer warranty or AppleCare, opening the case with a non-authorised part will void cover for that component. If the warranty has already expired (most phones people are repairing are 2+ years old), this is a non-issue.
Why does my iPhone show a "genuine part" warning after I replace the screen or battery?
Apple pairs the serial number of the original screen, battery and camera to the logic board. A non-Apple replacement part triggers a notification in Settings — it's informational, not a functional block, and the phone works normally including Face ID and True Tone on modern aftermarket screens.
How long does a screen or battery replacement actually take?
Realistically 20–45 minutes for a first-timer with the right tools and a video guide open, once you've got the part in hand. Flagship curved-screen Samsung models and any job needing heat to soften adhesive will run longer.
My phone still works but the battery health has dropped below 80% — is it worth fixing?
Yes, and it's one of the best-value repairs on this list. A worn battery is the single biggest drag on an otherwise healthy phone's day-to-day usability, and an £8–£10 cell buys another year or two of normal use rather than an upgrade you weren't planning for.
Can I fix a cracked back glass without replacing the whole battery cover?
On most modern iPhones the back glass is bonded to the frame as one panel, so a cracked back means replacing the full battery back cover assembly, not just the glass on top. Samsung A-series phones typically have a separate snap-off rear cover that's simpler and cheaper to swap.
What tools do I actually need to start repairing my own phone?
A precision screwdriver set (Pentalobe and Phillips for iPhone, Phillips for most Samsung), plastic pry tools, a suction cup for screens, and a SIM eject pin. A single 10-in-1 kit covers nearly every job on this page.
Is it safe to keep using a phone with a swollen battery while I wait for a replacement part?
No. Stop charging and using it immediately, keep it away from heat and flammable surfaces, and fit the replacement as soon as the part arrives. A swollen lithium cell is a genuine fire risk, not just a cosmetic issue.
Every part on this page is stocked and dispatched by The Repair Plus — we supply both DIY consumers and repair-shop owners across the UK, and every listing shows live stock so you're not ordering a part that's actually six weeks out. If you can't find your exact model, search the part name and your handset on the site or get in touch before you buy — we'd rather point you at the right connector than sell you the wrong one.