What Would It Cost to Build a Basic App That Connects Players to an External Game?

First define what the separate app actually does. Is it the game client, a launcher, a matchmaking tool, or a companion app that talks to a game server? If the game itself runs on a server, the app might only need authentication and connection logic. If it has to coordinate real-time gameplay, you’ll also need networking, synchronization, hosting, testing, and scaling. Those are very different projects, so the architecture should be explained before estimating cost.

There isn’t enough information for a meaningful price estimate yet. The cost depends on whether the app is just a login and matchmaking layer, whether it runs the game client, how the game synchronizes players, the expected player count, and whether you need voice chat, accounts, databases, anti-cheat, or persistent servers. A small class prototype could potentially use free tiers and take a weekend or a few weeks of development, while a polished public service can become expensive very quickly.

For a class assignment, it would be more realistic to estimate a limited prototype rather than a complete commercial product. You could assume existing libraries and cloud services, use their free development allowances, and calculate costs for hosting a small number of players. Then explain that production costs would include developer time, server usage, bandwidth, maintenance, security, customer support, and possibly platform fees. That gives a defensible estimate without pretending there is one universal price.