To transfer the progress from Steam to your mobile device, follow these steps:
1. Install the Plarium Play app from plarium.com on your PC
2. Tap on "Log in"
3. In the opened window, hit "Steam" to sign in to your current account
4. Agree to link your Steam and Plarium Play accounts
5. Tap on "Settings" in Plarium Play
6. Hit "Add email and password" and specify your new login credentials
Afterward, you can use the created Plarium ID to log in on your mobile device.