stuck on the galaxy s6 powered by android screen.

Hi there!

Try deleting clearing cache. Here is how to do it

1. Turn off the phone.
2. Press and then hold the Home and Volume UP keys, then press and hold the Power key.
3. When the Samsung Galaxy S6 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
4. When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
5. Using the Volume Down key, navigate through the options, and highlight ‘wipe cache partition.’
6. Once highlighted, you may press the Power key to select it.
7. Now highlight the option ‘Yes’ using the Volume Down key and press the Power button to select it.
8. Wait until your phone is finished wiping the cache partition. Once completed, highlight the ‘Reboot system now’ and press the Power key.
9. The phone will now reboot longer than usual.
10. Hope this helps!