Despite half the civilised world giving OnePlus so big a cold shoulder after their 'unusual' maketing techniques of the One that they made Mr Freeze look like Johnny Storm overheating, and even thought they thought they would get lucky a second time with an invite system that grew to do more damage than good, I was at the front of the queue to buy a OnePlus Two. When I bought the device there were very few reviews on the net other than from sites getting in quick with first look posts. Scare stories were everywhere, some fuelled by the audacity of OnePlus not to include NFC and other growing from the inclusion of the much maligned SnapDroagon 810 SOC. Being honest the SOC did concern me a little, but the other hardware choices I was fine with (I think I have used NFC once for anything other than messing about since I had my first handset with the chip). I was also not overly fussed about the stock software as job number one for me is to unlock and root. I knew that there would be a dev community springing up for the Two within a few weeks once the invite system trickled down to the talented ROM developers who don't carry much clout with PR folks. Sadly I was wrong.
For all the time I had my OnePlus One I used custom ROM's of one flavour or another after the second or third day. Because the device had shipped with Cyanogen and they also provided a community build every ROM I tried had full hardware support. Some of the overly cusomisable ROM's might have had some little niggles with additional software features but that would have been the case accross pretty much every device the ROM was ported to. It's hard to say which company benefited most from the ill-fated partnership on the One but in some ways I think OnePlus are suffering more since it's end. Not taking into account the PR disaster for both of the very public fall out, OnePlus are currently missing a vital ingredient of any quality unit, a good ROM. Oxygen OS just doesnt cut it. I didn't try Oxygen on my OPO, and maybe if I had I would have bought the OP2 with lower expectations. The ROM has been buggy since the start and I can't bring myself to believe it will get better. If OnePlus are true to their words and update the fingerprint sensor firmware to the Google API when they finally release Marshmallow then I get the feeling that a LOT of users will desert their stock ROM for a CM based one, as currently it isn't supported.
In a fit of curiosity I flashed the other official OP2 ROM a couple of days ago, Hydrogen OS. Hydrogen is meant for the far east market, and not being a big fan of the IOS styled ROM's (MIUI, Emotion UI etc) I didn't hope for much. I was expecting a ROM with a launcher and settings layout I didn;t like and a repeat of the bugs found in Oxygen OS. What I got was something far different, a far smoother experience, with next to no bugs that I can tell.
Apart from being more stable, Hydrogen has some nice little features that are missing from the Oxygen ROM, and vice versa, some of the nice touches included in Oxygen are absent from Hydrogen. A lot of these little features don't directly impact on the core OS so it strikes me as strange that they are missing even as an option. I am guessing that their are two distinct software teams working for OnePlus, one each for Hydrogen OS and Oxygen OS. If that's the case are they in competition or do they just not confer and try each others work? Is there nobody at OnePlus HQ looking at the work of both teams and suggesting that some of these features should be in both ROM's? If it's the result of a single software team then that's even worse, why would you deem a feature to be useful in one ROM but not another? It makes no sense to me at all.
Now to be clear I am not talking about differences like the two gallery apps, one of which is very AOSP for the west and the other more like MIUI's offering for the east. That kind of makes sense as consumers have voted with their wallets in each of those regions to say what they want. Little things however, like the ability to delete a screenshot from the notification bar (present in the Oxygen ROM, but not on Hydrogen) make no sense at all. Even worse is the performance of the unit. Running a rooted Hydrogen in comarison to a rooted Oxygen ROM there is no comparison, Hydrogen wins hands down. I mentioned in the review I did for Land of Droid that occasionally I would get little stutters, not so much a lag in performance but rather a slight delay before it would kick into life. I put thisdown to the way OnePlus dealt with throtling on the 810 SOC but it just doesnt happen on Hydrogen, everything happens instantly. Another difference is the performance of the fingerprint sensor. I have been lucky I think as I have seen a few folk complain of very hit and miss results when using it. For me, if I made sure the sensor was kept clean my biggest issue was the physical placement of it. It sits in a little 'bowl', depresed below the surface of the front screen and the depth is made worse when using a screen protector (something the OP2 ships with) which I believed meant that my finger wasn;t always making a proper contact with it. It was also slow in comparison to other modern sensors. Imagine my surprise then to discover that while using Hydrogen the sensor works roughly twice as fast and hardly misses a touch. Obviously the placement isn't an issue at all (or a very minor one at most) but in fact the problem comes with the ROM. It's so far down the line now that something that big shouldn't even be mentioned anymore, it should have been fixed long ago. On the subject of the fingerprint sensor another nice touch in Hydrogen is that a bad scan produces a diferent haptic vibration than a succesful one, again this is missing in Oxygen. Add to these better app permissions, auto app start manager, hybernation features baked into the ROM and more it's hard to see why they let Oxygen ship. Hopefully with Android 6 they will get a better cohesion between the two flavours.
Hydrogen isn't without it's little quirks, but they are fewer and mostly able to be 'fixed'. Changing the launcher or installing a 3rd party app works for most of it. That's why until Marshmallow drops I will be using Hydrogen, and would recommend any OP2 user to try it out for themselves, even if you can't delete screenshots from the navigation bar.