Great watch. I now have three gshock 2100’s including the new gmb2100d all metal watch from Japan. Love them all.
The yellow one is by far the easiest to read for my middle age eyes.
There are three different Casio apps in the App Store so make sure you download the right one. The app works well and you can control all the watch functions from the app.
Two of the watches came out of the box with the power setting at “M”. The other was at low but quickly moved to medium after being exposed to room light. I don’t spend a lot of time outside in the sun. When I have been in bright sunlight the power setting has moved to high but will go back to medium after I’ve been indoors for even a short period of time.
I suspect these 2100 model gshocks use more energy than my digital only square gshocks because of the analog hands. Indoor light may not be enough to fully charge the power supply and if i spent more time outside they would fully charge. As it is they work great and I love them.

LOVE it. I get more compliments on this watch than my more expensive watches. The yellow color really pops.

I don’t own anything this bright in color. I was a bit nervous at first but have been in the mood for the something colorful, all my other g-shocks are black or gray. Wow. The yellow of the strap pops, and the the white indices make a fantastic contrast. Definitely a looker! Great size and very comfortable! Easy Bluetooth setup through Casio Watches app as well! Most definitely recommend!

Well as you can see I did the conversion I bought the GA-B2100 on Amazon and the kit to make it look more like the royal oak. Kit on aliexpress. I paid like $23 bucks for it. I will that it give the G shock more weight than the regular version. I have two more G shocks 2100 coming this weekend and will use SKXM kits for those two. They’re more expensive but I will see the difference between them and aliexpress. I purchased 3 GA 2100 recently off of Amazon to convert into casioaks. Only My GA 2100 WS had the instructions in a book form. The other two Blue tooth models have a paper version. Now I have seen videos saying the ones like that are fake. How can I real know if that’s true or not. Seeing that both came the same way. Both boxes were the same size.
The none blue tooth box was larger I would think Amazon would insure that the prime sellers are legit. Something to consider and think about. Well the both Synchronized with the Casio app. So assuming that they are legit.

I must confess I already have the black version of this, but when I saw the yellow solar version, I had to have it. I got a good deal on it too. Fit's well. My favorite part about these is you just set the time zone and the hands auto set. It syncs time with satellite so you never have to worry about setting the time or DST. The light works well, you can see everything including the digital display it's closest too. If you like analogue style this is pretty much the last watch you'll ever need. Never break, and you'll probably never have to change the battery.

La correa del cacio chilla mucha, parece de plastico

Once you download the app, it will walk you thru setup, I watched a video on YouTube, there were very many, and it didn't take long and my watch moved the hands all by the connection. The yellow stands out, I'm not sure if I'll change that, this is a great value anytime you get a g-shock brand watch you get ultra reliable, very durable, night light, and glowing hands!