On the main screen in DiveMate, there is a FILE IMPORT option (mine is in the menu button of my galaxy s3, and top right corner of my nexus7) for dives currently contained in divelog5 or whatever, you need to copy them onto your microSD first. (it will be a .sql file exported from divelog5)
From there you should just select the .sql from the microSD card, and the app looks after the rest.
You do not need to import these before any future dives, since the app lets you alter the dive number at any time.
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