Some forms, such as that for Owen's Corning Roof Data Technician Program and Mock Inspections, will have a maximum file size requirement.
The photos must be under 5MB each. If some are larger than that, you will need to resize them. I have included links below with instructions:
Another option would be to use an app such as Google Photos to backup and store your photos. Google Photos offers many benefits, such as automatically backing up your photos and making them accessible across all of your devices, removing the need of having to email the images or transfer them to your computer. It also provides an option to store your photos at a slightly lower file size, which will remove the need to reduce the file size before uploading them. In addition to these benefits, you also will no longer need to store the photos on your phone, which will save a ton of memory.