PDF4Teachers is a free and open-source PDF editor
The app is based on recording of all annotations, which allow quick insertion of recurrent advices and corrections : each annotation added is saved in a list where one can pick previous annotations. The annotations can be written in LaTeX. It's possible to save different favourite lists in addition to the previous elements list.
The app offers functionnalities of grading, which allows to assess student's scripts faster : you can define a grading scale on a template document and copy it to other documents. The software shows automatically the next grade to pick, sub-totals and total are automatically calculated. It is possible to export the grades of a batch of documents in a spreadsheet (.CSV format).
PDF4Teachers also offers you a lot of usefull additionnal features, like the conversion of a batch of images in several PDF files, or rotation and pages shifting. Read more details with the documentation.
PDF4Teachers is not a business company. The app and the website are developped by a high school student, Clément Grennerat.
The code of the application is distributed under the license Apache 2.0 so you can edit it and reuse it in your projects, in agreement with the license conditions. You can use PDF4Teachers for a commercial use and you can distribute the app. All legal informations are available on the license page.
You can find more informations about dependencies and technologies used on the GitHub repository of the projet.
You can support the project with a donation. Either with a monthly donation with GitHub Sponsors, or a single donation on PayPal.