It may be all you need is this adapter, shown below..

Phone on Fence Shown with Wide Angle Lens

Adapter is shown to left by itself.  To the right, the adapter is shown mounted on the QM-1 "Quick Mount" Portable Camera Mount.  Phone is shown using a Wide Angle Lens (NOT INCLUDED), BUT this lens is available with the Smartphone Kit.

View from 18' setback, 10' high

View as seen using Smartphone, .45x lens and QM-1 Camera Mount.  Unedited except for captions.  Note:  Newer iPhones (11 and up) and some other phones have a wide-angle lens built in.  To test, stand at the back of a tennis court and look at how the court is covered by your phone.  If you can see the near corners of the doubles alley, you are probably good with just the adapter.  Otherwise, consider the Smartphone Video Package or if you already have a QM-1, then the Smartphone Kit which includes the adapter and a high-quality wide-angle lens.

Your smartphone may be the best camera you have!  GoPros and other action cameras are great, but your phone may also be the most convenient and reliable piece of equipment you have.

Shipping is added in the cart at $1.00.