When your refurbished phone arrives, spend the first hour confirming three things. The device is the one you bought, nobody else has it tied to their account, and everything works. Do it before the five business days the law gives you to cancel a distance purchase run out, and keep the box, the packaging and photos of everything until that window closes. If something fails, the shop's warranty and those five days are your two tools.
On iPhone, Apple no longer offers a public page to look up Activation Lock by IMEI or serial number, and the third-party pages that claim to do it have no confirmed accuracy. The only reliable way is with the device in your hand. Go to Settings > General > Reset (or Transfer or Reset, depending on the version) > Erase All Content and Settings. On restart, the device must not ask for someone else's Apple ID or password. If it does, the device is still tied to another account and only that person can release it.
On Android, Factory Reset Protection (FRP) ties the device to the previous owner's Google account. If that person did not remove their account before resetting, you are locked out at boot and the screen asks for their credentials. FRP cannot be removed remotely; only the account holder can do it, by removing their account in Settings > Accounts and resetting afterwards. To find out, factory reset the device and confirm that no screen appears at boot asking for someone else's Google account.
In Settings > General > About, since iOS 15.2, the Parts and Service History section shows whether the battery, display, camera or logic board were replaced. For each part it indicates whether it is a genuine Apple part installed with Apple's process, whether it is unknown (not genuine or faulty), and shows a separate notice when the logic board had previous service. If the section does not appear, nothing has ever been replaced, not even the battery. Only the most recent service for each part is shown. For a refurbished device this is the most valuable thing to look at, because it catches non-genuine displays, batteries and cameras.
On iPhone, go to Settings > Battery > Battery Health & Charging and read the maximum capacity. Apple considers a battery below 80% degraded, and that is the threshold at which AppleCare replaces it at no cost; below that point the device may also reduce performance because the battery can no longer sustain peak demand. Mercado Libre (the marketplace) requires more than 80% to list a device as refurbished, and no specialist shop we reviewed promises a higher floor, so 80% is the market's de facto standard. If the battery you were promised does not match what the screen shows, or if it reads below the 80% that Mercado Libre requires to list a refurbished device, you have a claim under the shop's warranty.
On Android there is no universal equivalent menu. Samsung, Xiaomi and Motorola show it in different places, so look up the steps for your brand and model. We could not confirm a path that works for all of them.
On the cost of replacing the battery at an authorized service center, a Mexican outlet reports 1,500 pesos for iPhone 12 through 16 in non-Pro, non-Plus versions and 2,000 pesos for Pro, Pro Max and Plus, VAT included, with a 3-month Apple warranty on the part. We did not confirm those figures on Apple's page for Mexico; treat them as a reference, not an official price.
iPhones have liquid contact indicators that are normally white or silver and turn red or pink if the device touched water or another water-based liquid. Ambient humidity within specification does not trigger them. Look at them with a strong light at an angle inside the SIM tray and, on older models, in the charging port. A red indicator voids Apple's coverage for water damage. On Android, the location and behaviour vary by brand and we did not confirm them.
A US iPhone 14 or later has no SIM tray; it needs an eSIM from your carrier and that is not a defect. A device that accepts only one carrier's SIM is locked and needs unlocking before it works with another. Both topics are in US, Chinese or European iPhone.
You have three windows, and it pays to use the one that favours you most first.
Go to PROFECO (the consumer protection agency) only once the shop and the platform have already said no. The path is in your rights when buying refurbished.
The battery prices come from a media outlet, not from Apple, and are not confirmed.
