Other members have mentioned great points.
A summary of mapping apps and software.
There are image acquisition apps that are installed on your device (
Smart Controller or phone).
These tend to be either a part of you flight software (DJI Pilot, Autel Explorer) or can be downloaded and installed (Pix4D Capture, Drone Deploy, Maps Made Easy, DJI GS Pro). These tend to be free and as stated are for collecting your images. For some advanced options you may have to pay to unlock them.
Next you will need software to "stitch the maps". These are Structure from Motion photogrammetry applications that do not run on your device (phone,
Smart Controller). These tend to be either subscription based (monthly, annually), Perpetual License or Pay as You Go. Examples being Drone Deploy, Pix4D, Agisoft Metashape, Reality Capture, WebODM.
Of the above photogrammetry software their payment methods are:
Drone Deploy: Subscription based with different plans for your needs
Pix4D: Subscription based with different plans, other software products and a Perpetual License
Agisoft Metashape: Perpetual Licenses
Reality Capture: Pay as you go, Perpetual License
Maps Made Easy: Free processing for small maps, subscription plans and Pay as you Go
WebODM: Free
Another factor is whether you will use the software installed on your computer or if you will use the software's cloud options.
If you go with processing on your computer, be sure to have a computer up to the task. These software programs tend to need a good processor, a lot of RAM and a discrete GPU, and an SSD drive helps too.
If using cloud options, know that if the cloud software fails processing or has issues with the outputs, you will not be able to address the underlying factors that caused this. With desktop processing you do have a chance to fix issues, but in the end, improperly obtained images will cause failed processing regardless of whether you use cloud or desktop processing.
