This would be very handy. 

Almost all iPhone users experience battery issues at some point of owning the device. Unfortunately not all of us are entitled to a free fix, but some iPhone 6s users are. Many people have been reporting issues with the phone where it will shut off or die completely even if the battery is not at 0%. Apple has has acknowledged there were some faulty phones among the all iPhone 6s made, and are offering a solution. The company is offering free battery replacements to customers who bought faulty handsets.

''Apple has determined that a very small number of iPhone 6s devices may unexpectedly shut down. This is not a safety issue and only affects devices within a limited serial number range that were manufactured between September and October 2015.'' A statement from Apple said.

Only certain phones are being deemed faulty,you can check if your phone is one of them by checking its' serial number. ‘'If you have experienced this issue, please visit an Apple Retail Store or an Apple Authorized Service Provider and have your device’s serial number checked to confirm eligibility for a battery replacement, free of charge'’ Even if you have already replaced the faulty battery and paid for it, the company is offering a refund. However, if your iPhone 6S has a cracked screen or features any other damage, you will have to get that repaired before getting the battery replaced.