With a Software Development Agreement, you hire a developer to develop and design a new and custom software for you or your company. In contrast, you use a software purchase assignment agreement to purchase an existing software. For the latter, you could either purchase a license to use the software or execute a transfer of the software with all the attendant intellectual property rights.
Changes and revisions are the most challenging part of software/website development. This is why it is essential to agree on the resolution of future changes before hiring a developer. Most developers will agree to a few changes for free as part of the project, but you may need to pay additional fees for unreasonable iterations to be defined in the agreement.
Yes. If you want someone to create a mobile app for you, you can use this agreement as a template. In the part where you provide a brief description of the project, you would specify the app that you want to order. There is also a separate document called the Mobile Application Development Agreement with very similar terms and structures, if you prefer to be very exact and proper.