Delete what? there are more options to delete stuff like workouts and forum posts/comments if you log onto skimble.com via your browser on your phone or on a pc.
You have to log on to skimble.com on a pc, or use your phone internet browser app.
On a PC it's easier, just log in and click on your name in the upper right to drop the menu, go to account settings and find the big red button.
If you use your phone, log in by clicking the lines box in upper right corner to drop the menu. Then look to the bottom of the page and click "full website" then you can drag the page over to find your name at the upper right corner, click it to drop the menu, go to account settings and there is the big red delete button for you.