A clean flash prevents bootloops and app crashes caused by conflicting data structures from the previous OS.
Team Win Recovery Project (TWRP) is the gold standard for custom recoveries. It allows you to flash custom ROMs, create full system backups (Nandroid backups), and wipe partitions.
As of 2026, development for the J1 Ace has largely shifted to XDA Developers and specific community members focusing on light, fast Android versions. 1. [UNOFFICIAL] LineageOS 14.1 (Android 7.1.2 Nougat) Daily use, performance, and compatibility.
Assuming you are in TWRP:
After the ROM installation is finished, flash the GApps .zip file.