You could synchronize them via a Dropbox sync store (see Preferences > Sync) and therefore use both Macs concurrently too. However, storing databases in the Dropbox folder isn’t possible.
under D2 on my old iMac under Yosemite, with my current license
Note: The purchase of DEVONthink 3 invalidates the license for DEVONthink 2.x. Depending on what edition of DEVONthink 3 you purchased, you likely can use it for DEVONthink 2. However, it will consume the second seat. This means you could not install 3 on a third machine without purchasing another seat.
Absolutely.
DEVONthink’s database file format remains the same between version 2 and 3. This means you can easily open your existing databases in DEVONthink 3, with no “conversion” or “migration” needed.
The database format is basically the same but it’s not recommended to edit the database directly using different editions, e.g. DEVONthink 2 is not aware of the additions of version 3. However, synchronizing databases between different editions is fully supported and doesn’t cause any conflicts.
@BLUEFROG
Thank you for the clarification.
I actually thought I could use the 2 licenses separately!
I currently have a DT2 PRO.
And I plan to buy a standard DT3.
Will I lose something when I switch from DT2 to DT3?
Nope. When you purchase 3, the 2 license is replaced. But you do get two seats - a per-machine license - so it covers installing on two Macs (as long as they are running the minimum operating system - currently, 10.11.6).
A DEVONthink 3 Standard should license DEVONthink 2 Pro (though I could be corrected by @hvolkmann on this ). See this page for more information…
But going to DEVONthink 3 Standard will definitely be less feature-filled than 2.x Pro. I encourage everyone to go for DEVONthink 3 Pro.
And as I have said for years: Remember that the price of the software is not an expense. (An expense is recurring, like gas and chai lattes!) It is an investment in your education / business / and maybe even your life (finances, genealogy, health records, hobbies or business ideas, etc., etc.)
This is even more true with DEVONthink 3.
Plus, you should have a discount for upgrading the 2.x license.
When you decide to upgrade, select ​DEVONthink Pro > Purchase ​to open our online store with upgrade options specific to your license.