Many releases ago the Inventor team implemented the save reminder (available & configurable beneath the Tools tab > Application Options > Save tab > enable Save Reminder Timer & specify minutes).
At the designated time increment, a message balloon will appear in the upper right hand corner reminding you to save your work. A link is also provided within the reminder that if selected will automatically save your files.
This accompanied by utilizing the Vault can be a life saver.
Yes, it's true but it's not the same... often I try some modifies on parts which I don't want to save...
Also, with some big assemblies, time to save is very long... If I have to spend 1/2 minutes (or more, for saving) every 15 (or less), I spend 10/15% of working time to wait...
An 'autosave' feature is a must! As previous commenters have suggested, the program doesn't have to overwrite the currently open files. Rather, it should create copies when the program opens and overwrite those instead every 'x' minutes or some other trigger (see Easy Tools). In case of a crash, the program finds the autosave files and asks the user if they wish to recover them. In addition to recovering each file at the point where the program crashed, the undo history is also recreated, overcoming any of the problems associated with a straight autosave to the original files. Plenty of other systems use this behaviour and it works well.
Save reminder is not a solution, only a helper... We need backups, not only to protect us from Inventor crashes, but from computer crashes, battery backup failures, etc... when a huge file is corrupted during a hardware failure, there is currently nothing you can do!
To those that think this should not be marked as Solution Provided you have to think why.
Inventor cannot save if you are in a command or in a sketch this is why it is posted Solution Provided
I don't know about you but if I was in the middle of a sketch or a command and Inventor booted me so it can do the save would just piss me off.