Seems like people in this thread are inspired by this novel concept that isn't novel at all.
FireChat was in fact used against dictatorial governments during protests in Iraq and Hong Kong. So it fits the aspired goal for the apps suggested here perfectly, and yet still failed as a product.
I'm positive on bioengineering carbon capture tech. Not aligned on investing in a land-based solution as ~70% of the Earth's surface is water-covered. Also, algae are already the fastest growing plants on Earth, before any genetic engineering.
From first principles, why not focus efforts on the most scalable and fastest carbon fixing planyts?
RE land-based vs ocean-based: true, ~70% of the surface is covered in a water, BUT most of that is relatively barren open ocean. The most bio-diverse and productive parts of the ocean are within a couple hundred miles of coastlines and underwater shelves/canyons etc. Ocean plants and algaes grow in a very very small portion of that ~70%.
Algae make more oxygen but they don't store it (unless you count them being eaten by progressively larger fish until the last one drops dead somewhere deep in the ocean). Make mangroves instead, best of both worlds.
