There are quite a few examples @martaalmela. Some of my favorites include
Uwazi: Is a free, open-source solution for organising, analysing and publishing documents. It has been used by organizations in different parts of the world to publish and share documents around human rights abuses, institutional violence and more.
EyeWitness project Allows organizations to capture and safely store verifiable media evidence for human rights abuses on their mobile devices
Open Data Kit: This is a free open source toolkit that allows users to setup a basic data collection and reporting system. It has been used by many organizations successfully particularly in resource constrained settings.
A key takeaway that legal empowerment organizations could learn from are that solutions don’t have to be complex in order to have an impact if they are solving the right problem. We encourage reusing methods or tools when it come to tech instead of building from scratch. In particular this saves a lot of time and resources. So this means doing research and getting a scope of the landscape can be very helpful in finding the right tool to use.