The best alternatives to Urlbox are App Review Monitor, Usersnap, and Hyperbeam API. If these 3 options don't work for you, we've listed a few more alternatives below.
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AssemblyAI— Speech-to-Text API with superhuman accuracy
The Hyperbeam API makes it easy for developers to embed real-time multiplayer capabilities into their web apps—including any other web app that you want to provide multiplayer access to.