One of the best cubes available today, that happens to have electronics inside that let you connect it to digital devices.
The Gan 12Ui is one of the best speed cubes ever made. Read that again and remember that this is supposed to be a smart cube.
I've tried my fair share of smart cubes in the past 2-3 years, and while some of them have been good smart cubes (e.g. Gan iCarry) and others have been great ones (Moyu AI, Gan i3), they have never been comparable to proper speed cubes. Even the best ones had some catchiness, some extra weight or some iffy stiffness that made them chunky and a bit unwieldy. They performed well enough to make sense for training and analytics (and for some people, competing online), but when you wanted to get your real times, you'd pat the smart cube on the corner and tell it to go back to its charging box while you chatted with the grown up cubes.
This is no longer an inevitability. I have been using the Gan 12Ui for the past month and it's become my main cube for normal solving (I've broken my PBs on both CFOP and Roux within hours of starting to solve with it).
It feels like a slightly heavier version of the Gan12. And given how light (and to some extent flimsy) the 12 was, this is actually a plus. This is just perception though, as the Gan12Ui actually only weighs 1 gram more than the Gan12 (68g vs 67g), leaving it far lighter than most other smart cubes, let alone body-positivity cubes like the Rubiks Connected. The weight distribution makes it feel as if the outer pieces have just a bit more heft than in the Gan12, even though the piece design is identical with the only difference being the core-corner magnets – which protruded massively on the Gan12 and tended to catch more than one might like – that have been shortened a lot to fit around the electronic core. (Fun fact, this is actually the first Gan to sport a Ball Core). The results is less catches, smoother turning than on the Gan12, at the price of the auto-align feature that is vastly reduced on the smartcube compared to its dumdum version.
I find myself liking this one a lot for Roux. Turning is effortless, corner cutting is truly forgiving and the weaker auto-align makes slice turns less snappy and softer. If I had a gripe, it is that at 56mm it feels a bit bulky for OH on my chubby fingers. (I still managed to lower my global average on OH with this thing).
Add in the UV coating (the only surface available, thank you very much), bright shiny colors and center caps with those techy indents for the Gan robot, and a more solid plastic that is closer to the Gan13 than the see-through plastic of the Gan12, and you have a cube that looks as badass as it performs.
An added benefit of this smartcube being so good as a cube in general? I don't care about battery life anymore : once it's out of juice, it remains one of the best cubes I have, instead of becoming a coloured brick that needs to wait for electrons to pour in. Not that I find myself with low battery often, mind you. On a full charge I can't really deplete the batteries in their entirety (my life doesn't let me cube for more than 4h straight anymore), so if you remember to store it in its box in between sessions you'll be perfectly fine. The only situations in which I ended up having low batteries were when I forgot to charge the battery box itself (it is a glorified 1000mAh powerbank that you can't use to charge anything else than a cube).
A discussion about software is not really germaine to this review. But it needs to be said that the cube can be connected to most modern cubing app that use bluetooth (Cubeast or Briefcubing to cite two). You need to obtain the MAC address of the cube itself from the GAN Cube Station app, but you can then leave that ghastly piece of software alone after that. Unless you like baroque user interfaces and you want to use it (in which case you'll be able to get gyroscope information about rotation, which you don't really get with, say, Cubeast).
The only true drawback is not a small one: If you live in the West you can't really buy it. The product is currently not marketed outside of China, which is why you can't find it on GAN's own stores, and have to resort to independent distributors on Chinese platforms to get one. Not a difficult thing to do but delivery times are long, AND customer support is mostly inexistent: The first copy I received had one of the 6 faces that was not registering/sending moves, which makes the smart part of the cube inoperable. Give credit where it's due, GAN support staff was super friendly and quick to respond, but said that the only way for them to be able to help was to send the product back to the seller in China. The realities of customs fees and shipping are such that it would have cost the same amount as buying the cube all over again just to have it repaired/replaced and shipped back. I ended up purchasing a second copy, that fortunately had no issues whatsoever, and am happily using the non-working version as a dumb cube for travels (plus I get an extra charging box for the office). Hopefully I was particularly unlucky and the 50% hit ratio for factory errors I experienced is not representative of the reality of quality control and technical failure of this cube.
The last point is one that needs to be considered in a GAN context : factor in shipping costs and customs fees and this cube costs between 140$ and 150$. That starts to be expensive even for people who have jobs. It is 2x the price of a flagship GAN cube, but it's nearing FIVE times the price of many other smart cubes. That is ridiculously expensive, but it is also a smart cube that stands on a tier of its own. I'll re-iterate : no other smart cube, from any brand (GAN included) comes anywhere close to the performance of this cube as a speed cube. It is going to be too expensive for many (most?) people. But if you can afford this, it is the current state-of-the-art in cube technology.
Would I recommend it to anyone?
If the risk of technical issues is indeed high, I would say no. I am lucky enough to have a steady source of disposable income that lets me sustain the hit of one very expensive cube for the sake of writing a review, but having to dunk almost 300$ on a non-collector cube because you were unlucky does not sound like a great deal. The very reasonable alternative is to wait for it to be released in the West. But given that the I3 and iCarry S have only recently been launched here, it might take a while before that happens (2024?).
With that said, if you were going to invest that money into NFT, then you might as well get the best smart cube in the world right now, and one of the best speed cubes available today.
UPDATE Q3 2023
GAN has released the Gan 12 Ui Freeplay in the west, which is basically the same cube but improved. Battery life has been increased to the point that you'll never really have to worry about having a charger with you (I'm charging this once every couple of weeks despite daily usage). The compression settings are slightly different (fewer options) so there's a tiny bit less nuance in the customization, but it's tiny details. If you can afford this, go buy one.