1. It's open source which supports range of languages, operating systems and languages. Well suited for Android and IOS mobile automation. Supports all kinds of apps, which makes it flexible and robust mobile testing tool 2. It is less appropriate where we need intercept network call to verify the API calls. Extensive coding experience is required to work Appium
Testlum is particularly well-suited for automating regression and functional testing in projects with a well-defined structure. For example, we’ve effectively used it to automate all testing processes for our education platform. Its unlimited integration capabilities and that we could add custom integrations helped us a lot. We’ve found that Testlum provides great support for all testing needs, and we have no problems maintaining test stability.
I would like to give 9/10 rating to Appium because of it can easily integrate with popular frameworks and CI/CD tools, as well as it is reliable, flexible and easy to use. The setup can bit complex in initial step, but once on configured it's very easy to use and enables stable and scalable mobile automation for real and cloud devices.
If you're an Apple developer, you use Xcode. It's practically a forced necessity. For system testing though, it doesn't have to be. You can have your development team focus on unit and integration tests in their platform and another team automate acceptance tests with a language they are more familiar with.