Can I freely use this API in an iOS / Android app?

GeoDev

I want to use this API to create a single layer map that is just going to use hitTest() to get a value from that layer based on location event (click, or locate) and saves that value to a global variable. I want to put that map in a React app that I'm going to publish on the Apple Store and Google Play Store; however, I'm worried that I'm going to get charged for the API calls f it is used or downloaded a lot. For my purposes I described above, is it possible to freely use this API with a published app if it hypothetically gets massively downloaded and used? 

JeffreyWilkerson

I don't know about developing for iOS, but if you can get Javascript to work in your environment then you can use the API.  You can also download the API which isn't that huge (not sure about where you will store it) so that you aren't having to download it each time a user hits your app.  I'd be more concerned with the online map that you'll have to be hitting.  That data will have to be hit each time the users access a map, and if any online analysis gets done that will need credits against some online account.  There are a lot of 'free' public maps to use, but if it's not your account millions (billions?) of hits a day could derail your desires to not pay for anything.