Immediately after the ROM, flash the GApps zip. Do not reboot between these steps.
Select Install , find the Lineage zip, and swipe to flash. lineage14120180419unofficialgtel3g fix
Navigate to Settings > Cellular Networks > Access Point Names (APN) and manually enter your carrier's settings. If the signal remains dead, ensure you have flashed the latest stock Samsung firmware (Lollipop) before moving to LineageOS to ensure your modem/baseband is up to date. 3. Google Play Services "Battery Drain" Immediately after the ROM, flash the GApps zip
While newer versions (Oreo/Pie) exist for some variants, remains the "sweet spot" for the Galaxy Tab 4. It provides the security of Android Nougat without the heavy RAM requirements of newer versions, ensuring your 3G tablet remains a functional media and browsing device. Navigate to Settings > Cellular Networks > Access
In TWRP, go to Wipe > Advanced Wipe and select: System, Data, Cache, and Dalvik .
Use OpenGApps (ARM / 7.1 / Pico) . The "Pico" version is the lightest, preventing the system from lagging under the weight of unnecessary Google background processes. Installation Steps Prerequisites: Unlocked Bootloader: Standard for the SM-T531. Custom Recovery: TWRP (3.0.0 or higher). The Files: lineage-14.1-20180419-unofficial-gtel3g.zip open_gapps-arm-7.1-pico.zip Magisk (Optional, for root access). Step-by-Step Guide: Backup: Back up your current ROM and data via TWRP.