This is not going to be the best answer, this is only what I do. I think it's quite difficult for regular users, but I post here because it's handy to me.
- I have all characters sheets of all games (including DH) in a very simple HTML format that looks good on a text editor and on a browser.
- Those character sheets are stored on a git server I have hosted. I think there must be some git servers for free use that you can use for that purpose.
- I have git clients on my computer and my mobile devices that allow me to ubiquitously access to the last version.
- BONUS: I have a script on the git server that puts the uploaded sheets and all the changes online, so I can access them from any device that has a browser, even if it has no git client.
git is a version control program that, like all of its kind, allow to store documents in all its versions, storing all changes, and lets you access how the document was at any time.
A simpler approach, but still a technical one, would be to use one of the multiple clouds available for use. Those applications allow you to automatically synchronize the documents on all devices, but usually allow you to operate them offline. I recommend owncloud for freedom and privacy issues, but it may be difficult to find/create a server for a regular user.
None of these solutions are character generators, and hardly managers. I said this wasn't going to be the best answer. But they're the solutions I use for the problems you posted.