#version_code: 20
- Improvement in downloading and opening files

#version_code: 19
- Improvement in receiving notification

#version_code: 17
- Cookie bugs fixed on old android version

#version_code: 15
- Notifications improvement

#version_code: 14
- Graphic improvement
- Using shared preferences mechanism to store cookies

#version_code: 4
- Add force update mechanism for some versions