Unity Android run in background

I am building a simple game where 2 people can duel against each other. I am using GameSparks as a back end. My problem is, that whenever player #1 casts a spell that is channeling, player #2 can see the channeling only when his screen is turned on and in focus.

Whenever player’s #2 screen turns off, the app is not active anymore so the spell is not being casted at him. When player #2 turns on the screen, the channeling starts, but player #1 was already done channeling a while ago.

I assume that is related to the way Android system works. It puts apps that are not in focus on pause.

My problem now is, how can I make sure that player #2 gets a notification whenever he is hit by the spell without a need to use any third party service to keep the app alive (to avoid huge battery consumption) and also without a need to use push notifications (as from what I’ve heard, if there is a high load, the push doesn’t happen right away, since there is a queue)

Thanks for any helpful answer!

I think there’s a reason why it’s not possible any other way. If your opponent wants to play, the game is up. If not, he must likely want to choose when to interact with the game. This means a game that requires instant responses from the player even outside the game is bad design. Notifications are the way to go: