Letsencrypt as you said, is still in beta , and the CA which signs your certificate is not trusted yet ( Maybe on December ) . So this has some implications as you cannot test it in mobile apps ( without including those certificates manually ) . So in other words not ready yet for production … But ,
If you want to be prepare and you want to try letsencrypt , you can do it ( with some effort from your side ) .
Some tips for installing letsencrypt on a ubuntu box ( Tested on Digital Ocean Droplet ):
git clone https://github.com/letsencrypt/letsencrypt.git
virtualenv --no-site-packages -p python2 venv
./venv/bin/pip uninstall setuptools
./venv/bin/pip install setuptools
./venv/bin/python setup.py install
If everything went ok, at this point you are ready to ask for a SSL certificate:
./venv/bin/letsencrypt --email firstname.lastname@example.org --domains yoursite.com --authenticator standalone auth
Later on, you have to setup nginx ( mine is 1.9.6 )
Please wait until i have some time to publish all documentation . The good news is i’ve already written it , but the bad news is i have to translate to english yet ( Now is in spanish ) .
I’ll try to publish ASAP ,
Hope this helps , at least to get letscrypt working