But maybe you are just asking about starting 2017 over..
But don't know if it can be done from the APP...or whether you have to log in to Online from a computer...thru the browser login to do it. (the "App" is just a second front end for the Browser-based Online software)
Even then, if you get to a certain stage....you may not be able to clear, and just need edit everything you mis-entered.
In TurboTax Online, you can erase your return and start from scratch as long as you haven't submitted payment, deducted the TurboTax fee from your refund, or registered.
- If you haven't already done so, sign in at TurboTax.com and select the blue Take me to my return button.
- On the welcome back screen, in the left-side menu, select Tax Tools, and then select Clear & Start Over (click or tap the 3 lines in the upper-left corner if you don't see this menu).
- Answer Yes in the pop-up to confirm.
After your entries have been cleared out, we'll prompt you to select a TurboTax product so you can start over from the very beginning.
If you're signed in under last year's login, we'll automatically transfer last year's info over if you select the PLUS upgrade, Deluxe, Premier, or Self-Employed. Federal Free Edition (without PLUS) does not include the year-over-year transfer feature.
If you can't Clear & Start Over after you've registered, and it's convenient, consider opening a new account under a new username. Up to 5 accounts can be tied to the same email address.
- Sign out of TurboTax Online.
- Select the TurboTax Online product you want to use for the second return and proceed.
- On the Create your account screen, set up a new login for the second return.
- You can reuse your email address if you want to receive e-file notifications for the second return.
- Up to 5 accounts can be tied to the same email address.
Otherwise, try to post another question about your problem and someone should be able to help you fix it.