custom Roms are also called AOSP roms which means android open source platform. roms are provided by your smartphones official website. if you want to change your os you can find many custom roms on google . but the main problem is that its not secure and it can distroy warranty of your smartphone .guys thats all at your own risk..
APPS WHICH WILL HELP AND PROVIDE CUSTOM ROMS -
In this article i am giving details about 2 apps which i think more secure and support finder for your smartphone so they are given down .
ROM MANAGER is a android app ,which will identify suitable rom for your device.thedownload link is here https://play.google.com/store/apps/details?id=com.koushikdutta.rommanager
2.GOO MANAGERThis works same as the rom manager . you can search on the google and download this app.
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