Some problems

Hi, as I already said in the review on the Play Store, you should upgrade the server, because online (mobile browser) it's terribly slow, with punishing lag (I lose games because I'm denied the checkmate move, due to slow processing and response times—and my opponent may only have one pawn blocked!). For the sake of clarity, it should also be noted that Google is doing everything it can to penalize and decommission older devices (I have the impression that the processors are slow, and since Google is the only one that keeps writing on my device...). However, it also depends a lot on you, because, for example, on the FICS portal the game is fluid—and you can even retract premoves there.

But here I'd add that you should also review the program's algorithm, including the analysis phase, because it causes inconceivable bugs and slowdowns, as you can see in the example below—the arrow makes no sense, the position is won by White.:

Upgrade your server and I would buy a subscription. Not the way it is now.

The site has modern servers and is constantly working on improving code to minimize issues

If your device is older, as mentioned in your initial post, that could cause additional slowness and problems, especially when using the site on a mobile browser.

You should try on the app to see if that improves things.

Cancelling premoves is possible here as well. It's harder on mobile web though.

https://support.chess.com/en/articles/8562432-what-are-pre-moves-and-how-do-they-work

Yes, I think Google has severely penalized users by not optimizing Play Services for their "outdated" devices, slowing them down. In the past, major brands have been targeted for similar planned obsolescence practices. Now I wonder, if the experience was seamless five years ago, what has changed now? The game's algorithm must surely be the same, the language JavaScript, I think, so is the blame solely on the induced software devastation? I don't understand how an outdated browser can be so incapable of interfacing with the site: new technologies, syntax, or what else? On FICS, it's seamless.

All phones are downgraded when the newer models come out. Get a laptop and try there. Also check the heating and WiFi. I had that problem when I used a minimal "phone" but it works seamlessly on a PC for me.

Also contact a tech expert if the issue persists, maybe you can get your phone or WiFi fixed.

A subscription does not fix this, and neither would new chess.com servers.

In fact, that's exactly what I meant, and what makes me furious: damaging the "old" to make room for the new. I was planning on trying it on a Windows tablet with a very up-to-date browser, but I haven't had a chance yet. It will most likely work fine and be responsive there, without the incredible lags and freezes I'm experiencing on my "antique" smartphone. I'm sure a subscription wouldn't solve this: these are objective and independent physical mechanisms!

Allow me just a thought on my device and the senseless disposable model. Back in the day it was top, made for 3D gaming, but then the bigwigs decided to tear it down and bury it = during the launch phase, fireworks and performance as expected, then from the stars to the stables... I know it's a war against windmills, lost from the start, but I say well!!

Notice however that the chess.com support explicitly tlold me that the site wasn't optimised for mobile environment, independently of the age of the device, and you can experience that, among other, in playing chess variants.

Looks like you got the solution, or at least know it. I don't have much else to say, hope you can get it fixed!