Using Unity and hitting “Build’n Run” will install on only one device. If you just build your APK, you’ll be able to install it on multiple devices by using:
[pastacode lang=”bash” message=”” highlight=”” provider=”manual”]
adb devices | tail -n +2 | cut -sf 1 | xargs -I X adb -s X install -r pathtogame/game.apk[/pastacode]
Having problems? Try this post on Stack Overflow.