Does Fone4u offer a warranty on refurbished/second-hand smartphones?

Yes, we offer a 18-month warranty on all refurbished/second-hand mobiles, such as hardware and functionality issues not resulting from accidental damage.

Can I trade-in my old mobile phone with Fone4u?

Yes! Sell your mobile stress-free with Fone4u. Get a quote instantly on our Sell Your Phone page, and hand in or post your device for rapid payment.

Does Fone4u repair phones and tablets?

Yes, we have expert repairs for iPhones, Samsung, iPads, and more, including screen repair, battery issues, and diagnostic work.

We are located at Tolan Street, Ballina, Co. Mayo, F26 XT02, Ireland. You can also visit us at the Sligo Co. Sligo store or the Bray Co. Wicklow store for purchases, repairs, and trading in your devices.

How long is delivery when I shop online?

We provide next-day delivery throughout Ireland on orders received up to 1 PM. Delivery is usually 1-2 working days from your location.

Which payment options does Fone4u provide?

We provide all major credit and debit cards, PayPal, American Express, and in-store payments.

Are the second-hand phones unlocked?

Yes, all our second-hand phones are completely unlocked and ready for use with any Irish or foreign network.

What if I change my mind after I've bought?

We operate a 14-day money-back guarantee on online purchases. If you do change your mind, simply return the phone in its original condition for a refund or exchange.

Do you deliver tech gadgets across Ireland?

Fone 4 U delivers new and refurbished best-brand tech gadgets securely and efficiently to customers across Ireland.

Are your refurbished items guaranteed?

Yes, all refurbished iPhones, Macbooks, laptops, tabs, iPads, AirPods, Smartwatches, Air Buds, Airpods Max and Accessories we offer are guaranteed, giving you peace of mind in your purchase.

What brands does Fone4U sell?

Fone4U sells Ireland's best technology brands like Apple, Samsung, Google pixel, Dell, Hoco, HP, Tronsmart, Redmi, Poco, Marvel, QCY, JBL, Lenovo, Joyroom, Xiaomi, OnePlus, Huawei, and many others at competitive prices.

Is it possible to buy accessories with my phone on Fone4U?

Yes, Fone4U also offers a range of accessories like phone cases, chargers, and AirPods so that you can get the purchase done all in one location.

Should I buy a refurbished phone?

Actually, buying refurbished from Fone4U allows you to save without losing on features or warranty. You receive a thoroughly tested, cleaned, and warranted phone with the latest features.

Aaliya Yousaf
01 Jun, 2026

The Complete Guide to Refurbished Phones: Testing, Battery Health & Grade A Explained

Thinking about buying a refurbished phone? You're making a smart move. But with terms like "Grade A", "80% battery health," and "fully tested" appearing on every listing, it helps to know exactly what those words mean—and what standards you should hold any seller to. This guide gives you the full picture, straight from the team at Fone4U.

How Refurbished Phones Are Tested

A refurbished phone is only as good as the process behind it. At Fone4U, every handset that comes through our doors goes through a rigorous multi-point inspection before it ever reaches a customer. Here's exactly what that process looks like.

Step 01

Initial intake & diagnostics

Every device is logged, assigned a unique ID, and run through diagnostic software to flag hardware faults before any manual inspection begins.

Step 02

Screen & display test

Technicians check for dead pixels, touch sensitivity, brightness, color accuracy, and any signs of burn-in or delamination.

Step 03

Camera & sensor check

Front and rear cameras are tested for focus, clarity, flash operation, and video recording. All sensors—proximity, gyroscope, and accelerometer—are verified.

Step 04

Battery health assessment

Battery capacity is measured against the original manufacturer specification using dedicated battery analysis tools. More on this below.

Step 05

Connectivity & signal test

Wi-Fi, Bluetooth, 4G/5G, NFC, GPS, and USB/charging ports are all tested under real-world conditions.

Step 06

Software & IMEI check

The device is confirmed blacklist-free, factory reset, and verified to accept the latest OS updates. iCloud or Google account locks are checked and cleared.

Once a phone passes all six stages, it's graded based on its cosmetic condition (not performance — performance is pass/fail). Any device that fails even one functional test is either repaired or removed from sale entirely.

Why this matters

Many cheaper refurbished sellers use a single automated scan and skip manual inspection entirely. At Fone4U, every phone is checked by a trained technician — not just software. That's the difference between a phone that works on day one and one that fails within weeks.

✔ Screen tested for touch accuracy & dead pixels
✔ Every button & port physically tested
✔ Factory reset & OS update confirmed
✔ Face ID / Touch ID / fingerprint sensor verified

✔ All cameras checked front & rear
✔ IMEI verified clean on international database
✔ Speaker, microphone & earpiece tested
✔ Charging speed & cable port inspected

How Battery Health Is Measured

Battery health is one of the most misunderstood specs in the refurbished phone market. Here's what the numbers actually mean and how reputable sellers — including Fone4U — measure and report them accurately.

What is battery health?
A smartphone battery degrades with every charge cycle. Battery health is expressed as a percentage of the battery's current maximum capacity versus its original design capacity when new. A brand new iPhone, for example, has 100% battery health. After 500 full charge cycles, that figure may drop to 80–85%.

BATTERY HEALTH TIERS EXPLAINED

Excellent (95–100%)Like new

Good (85–94%)Strong daily use

Fair (75–84%)Light-moderate use

Poor (below 75%)Replacement advised

How is it measured?On iPhones, battery health is accessible directly in Settings > Battery > Battery Health. For Android devices, technicians use third-party diagnostic tools such as CPU-Z, AccuBattery, or manufacturer-specific service menus (e.g., Samsung's *#0228# code) to read the current maximum charge capacity in milliamp-hours (mAh) and calculate it as a percentage of the original spec.

What should you look for? At Fone4U, we list the battery health percentage on every product page — no guesswork. Our Grade A phones carry a minimum battery health of 85%, which means a full day of normal use for the vast majority of customers. If a phone's battery is below this threshold, it either receives a replacement battery before sale or is graded and priced accordingly.

Insider tip: Always check battery health before buying. If a seller cannot provide it, that's a red flag.

Does lower battery health mean the phone is bad? Not necessarily. A phone at 82% battery health is still a capable device—it simply means the battery holds slightly less charge than new. Many customers are happy with phones in the 80–84% range, especially at a lower price point. What matters is that the seller is honest about it, and that's exactly what we are at Fone4U.

What Is a Grade A Refurbished Phone?

Grade	Cosmetic condition	Battery health	Functionality
Grade A	Minimal to no visible scratches. No cracks. Looks near-new from a normal viewing distance.	85% or above	100% fully tested & working
Grade B	Light scratches on the body or screen. No cracks. Signs of normal everyday use.	80% or above	100% fully tested & working
Grade C	Visible scratches, scuffs, or marks. Possibly a hairline crack on the rear glass.	75% or above	100% fully tested & working

The key insight here is that grading is purely cosmetic. A Grade B phone works just as well as a Grade A phone — it simply has more visible wear.

The Grade A standard means: no visible scratches, 85%+ battery health, fully tested, IMEI clean, and warranty backed.

Frequently Asked Questions

Functionally? Absolutely. A Grade A phone passes the same hardware tests as a brand-new device—every button, sensor, camera, and port is verified to be working. Cosmetically, you might spot the odd micro-scratch under a harsh light at very close range, but in everyday use, it looks and feels brand new. You get the same experience at a fraction of the price, which is honestly the whole point.

The grilles are purely cosmetic—they have nothing to do with how the phone performs. Grade A looks near-new with minimal signs of use. Grade B has light scratches from everyday wear. Grade C has more visible marks or scuffs. Every single grade goes through the same full 60-point functional test before it's sold. So if you're planning to use a case anyway, a Grade B gives you identical performance at a lower price.

This is a big one. "Second-hand" means someone is selling their old phone as-is—no testing, no cleaning, no checks, no warranty. What you see is what you get, and sometimes what you get isn't great. "Refurbished" means the phone has been professionally inspected, tested on every function, repaired where needed, and wiped back to factory settings. At Fone4U, every refurbished phone also comes with an 18-month warranty. That peace of mind is the real difference.

Yes — as long as you buy from a reputable seller. At Fone4U, every iPhone is IMEI-checked against international blacklists, fully unlocked, factory reset, and covered by an 18-month warranty. You're protected both by our own guarantee and by Irish consumer law. The risks come from buying off unverified marketplace listings—always buy from a seller who can tell you exactly what tests were done and show you the battery health.

For an average user, 85% will suffice, as you will be able to fully utilize the battery life in one day without any problems. For heavy users who are playing video games, streaming, or even navigating, we recommend getting one with 90%+. All Fone4U Grade A phones come with a minimum of 85% battery health, and we publish the exact figure on every product listing so you always know what you're getting before you buy.

It's quite easy for iPhones. Go to Settings → Battery → Battery Health and Charging, and you will find the percentage there. In Android phones, it differs from manufacturer to manufacturer. Samsung users can dial *#0228# to access battery info or use a free app like AccuBattery, which will show you the current capacity in mAh versus the original spec. If a seller won't tell you the battery health upfront, that's a red flag—walk away.

Yes, absolutely. A battery is one of the most straightforward parts to replace on a smartphone. If your phone's battery health drops further down the line, a qualified technician can swap it out and bring it back to near-new performance. Fone4U offers a battery replacement service — just drop us a message, and we'll sort you out. It's a much cheaper option than buying a new phone.

Yes—every refurbished phone sold at Fone4U comes with an 18-month warranty included as standard. If a hardware fault develops during that period, we'll repair or replace it. No drama, no small print gymnastics. We stand behind every phone we sell because we've already tested it thoroughly—we're confident it'll hold up.

Get in touch with us, and we'll take care of it. Within the 18-month warranty period, any hardware fault is covered — we'll repair or replace the phone at no cost to you. Outside of warranty, we also offer a repair service for the most common issues. Either way, you're not left on your own. You're also protected under Irish consumer rights legislation, which gives you additional cover beyond our own warranty.

All phones sold at Fone4U are fully network unlocked unless a listing specifically says otherwise. That means they'll work with any Irish carrier — Vodafone, Three, Eir, Tesco Mobile, Virgin Media — and any international SIM if you travel. No need to call anyone, no unlocking fee, no waiting. Just pop in your SIM and go.

Yes. Every iPhone we sell is verified to support the latest available iOS version for that model before it leaves us. There are no software locks, no blocked updates, no carrier restrictions. It behaves exactly like a phone bought directly from Apple — because as far as iOS is concerned, that's exactly what it is. We also confirm that iCloud Activation Lock is fully cleared, so you're starting with a completely clean slate.

Right now we stock the iPhone 17, iPhone 16, iPhone 15, and iPhone 14 — so whether you want the very latest model or a slightly older one that still punches well above its price, we've got you covered. Stock changes regularly, so if a specific model or storage size isn't showing, it's worth checking back or dropping us a message, and we'll let you know when it comes in.