Xiaomi miui is one of the best and most customizable android roms and although xiaomi dont provide google apps integrated with roms out-from-box in this thread you can download the smallest gapps packs which dont affect ota support (all additional desired google apps can be installed from google play store)
Notices : for gapps flashing you will need any custom recovery (cwm,twrp,…), Click here to watch the video.
Disclaimer:
We and the developer of this root procedures shall not be held responsible if any undesirable outcomes may happen to your devices caused by flashing any of this gapps packs. use of this update guide is solely at your own risk!
BASIC GAPPS FLASH TUTORIAL
1. Reboot device to custom recovery.
2. Select [install zip from sdcard] → [choose zip from sdcard]→ [xxx-gapps.Zip] → [yes]
3. Wait till flash finished, press back and select reboot system now [], the phone going to automatically restart with installed gapps.
DOWNLOAD GAPPS
Android 2.3.x
GB-GAPPS.zip (4.3 MB)
Android 4.0.x
ICS-GAPPS.zip (9.7 MB)
Android 4.1.x
4.1.X-GAPPS.zip (11.17 MB)
Android 4.2.x
4.2.X-GAPPS.zip (15.47 MB)
Android 4.3.x
4.3.X-GAPPS.zip (29.32 MB)
Android 4.4.x
4.4.X-GAPPS.zip (19.72 MB)
Android 5.0.x
5.0.X-GAPPS.zip (42.28 MB)
Root XiaoMi Redmi 1S:
UnRoot XiaoMi Redmi 1S:
Install Android Lollipop 5.1 on Xiaomi Redmi 1S:
Install Android 4.4.4 KitKat on Xiaomi Redmi 1S:
[Source: en.miui.com]