Save player's data to a server's database or cloud. How?

I am making a mobile single player game (no multiplayer, no networking; just a simple character that collects coins upon killing enemies).

Let’s simplify the game’s mechanics: it’s just a 3d character walking around and picking coins. These coins need to be persistently stored somewhere in a server, so that when the player closes the game and opens it back up, the number of coins she previously collected is still there.

Right now, I’m saving the player’s coins in my own implementation of a GameInstance (which I called BP_GameInstance). I called the variable “Coins” of type float. So far so good.

Now I’m wondering what’s the best service to use along with UE4 that makes integration easy if possible (using Blueprints).

I wouldn’t like to store the coins inside of the phone, since I’m trying to avoid easy ways to “hack into” the game and change the amount of coins collected. In a (far) future release I might want to monetize the game, so an anti-cheat method is required.

TL;DR: What online service/cloud should I use for a single player game (no multiplayer interactions), that I can possibly integrate with Blueprints?