What is the problem? Please be detailed.
I have a form with 5 pictures.
I left the camera settings to high resolution (13MB).
It takes me around 2 minutes to submit a form, but in the meanwhile I'm blocked to fill a new blank form.
What ODK tool and version are you using? And on what device and operating system version?
ODK Collect v1.16
Samsung, J7neo, versión Android 7.0, Camera 4:3 13MP
@aurdipas it sounds like this is with a manually-triggered submission, is that correct? That is, the user goes to Send Finalized Form, selects the form and sends it? That is a blocking operation. If high-resolution images are required, another option would be to turn on auto-send and this should mean submissions are sent in the background and a user can continue filling forms.
If high-res images aren't required, @Grzesiek2010 has the best solutions.
That means there's a problem. When you say "I'm blocked to fill a new blank form", where exactly are you blocked? Is it on the screen that saves a finalized form? Somewhere else? What if you put your device in airplane mode, save and finalize the form, and then turn airplane mode off? Does it still hang?