If you are still holding onto a device running , you know the struggle. The hardware might be aging, but your need for modern apps isn't. Google stopped auto-updating the Play Store on Lollipop devices years ago, leaving millions of users stuck with an outdated, laggy, and often broken marketplace.
Download a free app like Droid Hardware Info (if your Play Store still works) or check your phone's manual. For Android 5.1.1, 99% of devices use: