how to deploy apps developed in virtual env
Uploading your virtualenv probably won't work.  There is a good chance that something in the virtualenv is dependent on the exact file paths and versions that won't match from your machine to the virtual host.
You can upload the virtualenv tool, make a new virtualenv, and then install the version of flask you want inside that virtualenv.
I have a flask based app, and it's now running with virtualenv on my dev machine. Now I want to deploy it to my virtual host. Sadly, this virtual host is running flask 0.6, and I want flask 0.10. I don't have enough privilege to upgrade it. 
Can I just upload my whole virtual environment, and to use my own version of flask, and how? 
My idea is change the PYTHONPATH, how to get rid of the old version and add the new into it?
Any help will be appreciated.