I went for Beko. I wouldn't overthink - I'm sure they are all much of a muchness.
I wanted to avoid any of the Hotpoint brands (which Hoover is) in case of the fire risk - maybe paranoid of me.
AEG/Zanussi (Electrolux), Beko, Samsung, Siemens/Bosch, or LG - I'd just look for any of these brands within your price range. When I'm shopping for something like this I tend to look at the price comparison websites because a lot of the time the RRP/actual price is totally nonsensical - look at what it actually sold for previously. There is always something on sale somewhere.
Be aware energy ratings have changed so the A+++ ones are less efficient than the ones with a new rating of A or B. Check which energy rating scale it goes up to.
Direct Drive motor is worth having as it decreases wear and tear on the moving parts of the machine.
If you have access to the Which? ratings then I found it helpful to see what they said overall about different brands - you can get a sense of a theme.
Beko seem to be the best value option, as in they do cheap well, Siemens/Bosch are reliable and you can't go wrong with them, Samsung is very flashy and normally overpriced but can be decent in a sale because they sometimes have massive reductions. AEG/LG seem to be mid range brands that again you can get a good deal on in a sale. There are higher end brands which are good but you won't get for under £500.
Figure out which retailers you'd be happy to order from - you usually find a lot of them add on a huge amount for delivery/installation if you want that, so narrow it down this way, and that will reduce the choice likely to a small enough number that it's easier to make a choice anyway.
I only have two slight annoyances with my Beko - it has a light which turns on when you open the door but turns off much too quickly so it's useless for anything, and it has an anti-crease function that tumbles the clothes every 5 mins or so after a cycle is finished, or while it's waiting for a time delay start, and you can't turn this off. I find this annoying because I don't think it does anything, and furthermore the noise is irritating. I can turn it off by physically pressing the off button.
Oh, also, the touch sensitive buttons are forever getting activated when people reach across the counter, which means we have to put the child lock on all the time, but my new washing machine has exactly the same problem so I think this is just the curse of touch screen buttons which are now trendy for whatever reason.
You don't need an app, don't pay extra for one. Totally pointless because an app can't load/unload laundry for you. Though this feature now seems to be standard enough that I got one with my washing machine and I do quite like being able to track how much energy different cycles use, but that's literally the only useful function that it has.