Straight line on IPad Pro app with photoshop

Hi,

Like you, I have been wanting to draw a straight line in Photoshop on iPad Pro. 
This is my solution. 
If you select the TEXT tool. the keypad will appear. Do not insert any letters, but instead go to the numbers on the keypad (.?123 key), then go to the uppercase key (#+= key). This will give you access to the underline key, which is below the 4 and 5 numbers. Type a series of these to make a straight line. After this you will be able to change the thickness (Font size) and length (horizontal scale) and colour.  
You can then change position, angle and size by using the transform tool on left of screen.  
This all sounds long winded, but it only takes a second. 
I hope this helps..

I don't think there's a ruler in Photoshop (there's one in Fresco). You can create a rectangular selection and fill, but this is probably not a good solution. Use a physical ruler...? 😉