Expert in Automated App Testing with Appium

I need an experienced Automated QA specialist who can write test cases as user journeys, and then automate these tests using Appium. The tests should be able to run on both Android and iOS platforms using BrowserStack. Eventually, I will need you to perform API testing as well based on the budget and outcome.

Key Requirements:
- Proficiency with Appium for automated app testing
- Experience in writing test cases based on user journeys
- Ability to conduct testing on both Android and iOS platforms
- Familiarity with BrowserStack for cross-platform AUTOMATED testing