Samsung Galaxy Express 2 (SM-G3815) Firmware Overview
What is the latest SM-G3815 firmware?
G3815XXUCNL2, released April 27, 2015 for region PRO with Android 4.4.2. The archive holds 2 official builds for this region.
Is the Samsung Galaxy Express 2 still getting updates?
Most likely not: there has been no new firmware since April 2015, so Android 4.4.2 is the last version this model got. The final builds below are still the best choice for a clean reinstall.
SM-G3815 firmware for region PRO
How to Flash SM-G3815 Firmware
Put the Samsung Galaxy Express 2 into Download Mode, load the BL, AP, CP and CSC files into Odin on a Windows PC and press Start. Use HOME_CSC to keep your data, CSC for a full wipe.