Progress bar in a multi-page form in an app

We have an app wherein we need to ask a number of data from the user. We have split this into multiple pages and we put a progress bar on top.

However, because of the screen estate, we can only indicate the percentage of completion and not the actual steps involved.

However, using this method, the users cannot go back to the other parts of the form in one click. They have to click "Back" all the way to go to the previous parts of the form.

Is there a better way of doing this?