Hi @sheramin! It looks like ODK Collect's Persian translations are only 4% complete. You can help with the translations by going to https://www.transifex.com/opendatakit/collect/ and contributing to the Persian translations. Try it and let us know if you run into any problems!
Also, when you get a chance, please introduce yourself here. I'd also encourage you to add a real picture as your avatar because it helps build community!