Updated 9-23-19
- Adobe Reader–free
- Annotat8–lots of options; free
- DocHub–
- Foxit
- Goodreader–fee
- iAnnotate–fee; open Google Drive documents in iAnnotate
- iOS Mail App for iPads and iPhone (built in–limited tools, but useful)
- Kami–open PDF in Google Drive, then open with Kami (app)
- Lumin–open PDF in Google Drive, then open with Lumin (app)
- Notability
- Pinpoint–mark up screenshots; free
- PointOut–zooms in on a screenshot
- Skitch–annotate screenshots
