Has your iPhone been dying quickly? Will it not hold a charge anymore? The thing about iPhones is that there are multiple components that go along with the battery percentage. Your problem could be the charging port, it could be the Tristar Chip, or it could be your battery. Instead of wasting money on new battery after new battery, test it first. This tester is very useful and can be used to check the battery on iPhones 4G all the way through the XS Max and it could be used to check iPad and Apple Watch batteries: iPad Pro 12.9, iPad Pro 9.7, iPad Air 2, iPad 3, iPad 4, iPad Mini 1-4, Apple Watches 1-3. This tool is great for repair shops as well, it could be used to check multiple batteries at once and you won’t waste any time installing a faulty battery. It will bring your customer service up and the complaints of a bad battery down.