The settings in Textra has a section of changing the mobile number (Sim), but even if you change the number it still texts from the Sim number. I use my Google Voice number as my main phone number now and it would be Awesome if you can choose which phone number to make and receive texts from. For security issues, it can make you verify that the number is yours. I just absolutely LOVE Textra and I hate that I have to message through the plain old Google Voice app. PLEASE consider allowing us to make Textra the messaging app for other phone accounts! The option of having a second line on your cell phone through other apps such as wifi calling apps and the Google Voice app is becoming more and more popular and I think it can be a fantastic upgrade to make Textra stand out even better compared to other messaging apps. (not that it's already the Best messaging app already!) Thank you for taking this idea into consideration!