There doesn't seem to be any well organized collective details on the firmware changes. Near as I can tell, besides some bug fixes, much of the effort has gone to making the communication and info transfer between User, the Particle Cloud and the Oak smooth and robust. One real reason to move to 1.0.5 is that this allows a lot fewer trips to the Oak config app to reset the WiFi communication parameters. Goal is to allow recovery and/or re-programing of Oak whenever something goes awry. Your WiFi goes down and your Oak looses connection -- early firmware abandoned the selected WiFi parameters and just waited for a re-configuration. Particle cloud goes down and no graceful recovery.
From 1.0.2 to 1.0.4, this goal seems to have been corrupted by the behavior of the Particle cloud and the Oak device tended to fall into loops of going online and offline every second or two -- and being unresponsive to any OTA communication. This got straightened out a lot with 1.0.5.
With 1.0.5 and the now available OakTerm (
http://rawgit.com/kh90909/OakTerm/master/index.html Log in as to Particle login), we have a decent place to move forward. Error recovery and ability to maintain OTA programming access are fairly solid. For example, from OakTerm, you can switch to config mode and back with your program resuming running. You can do a reboot of your Oak from OakTerm. When in config mode, you can access the few direct Oak API links described here:
https://digistump.com/wiki/oak/tutorials/internalurls These allow verification of firmware versions, ID etc. You can re-program from config mode -- either entered this way or via a Pin1 to ground power cycle.
Between 1.0.1 and 1.0.5, at least the Blynk library has been updated. The firmware releases not only update the Oak core firmware, they come with a host of libraries/program modules that may also be updated. Using Arduino IDE 1.6.9, you can regress from 1.0.5 to 1.0.1 and hopefully such movement will be maintained. (Unfortunately, you can also load 1.0.2 or 1.0.3 or 1.0.4 but I would not recommend that unless you really want to learn how to do a Factory Restore over a USB Serial port).
This is a complicated three way system and still being invented on all three legs -- Oak, Particle and the User software -- mixed in with WiFi and the internet. There have been bumps, but I think you can beneficially move your base point to 1.0.5. Hopefully, newer changes will be better documented as the small team attacking issues at Digistump gets a fairly stable base to move forward from.
In essence, IMHO move to 1.0.5. Forget about ever loading 1.0.2 to 1.0.4. You can revert to 1.0.1 from the Arduino IDE 1.6.9 and the Board Manager if you ever feel the need.
You get better recovery from WiFi interruptions, code crashes, Particle software changes and such. OakTerm provides useful tools in 1.0.5 but not 1.0.1 (see
http://digistump.com/board/index.php/topic,2302.msg10960.html#msg10960 for details). Some third party libraries are updated in Oak firmware downloads or provided in Oak specific versions.
Let others try newer releases and move to them when they are not generating lots of Forum activity for problems. Or when a feature you need is documented as having been added.
Share what you learn that works well with others here and it all moves forward a bit faster.
Cheers
James