I need a new router because the current one is dropping its connection way too often.

Here are my requirements, as they currently stand:
* Must be configurable via a web interface. (In particular, configuration must not require a smartphone app.)
* Needs to be able to handle 25+ devices simultaneously. (There's like a dozen devices connected at any one time, and more capacity is needed for visitors.)
* Must be relatively cheap.
* (Mesh networking is something worth considering, as the part of the house furthest from the base station sometimes has some difficulty maintaining connection.)

So, any suggestions?

Have you tried reuters.com?


Boom boom!

You will likely want Gigabit Ethernet ports, the number of which should be determined by the number of locations which you wish to have great signal. Just run cables (Cat-5 should do depending on your internet speed) to the location(s) and hook them to access points which may also be purchased inexpensively and will effectively extend your network.

How about Keenetic Viva?

Are you open to custom firmware?

I picked up some Ubiquiti hardware this year and it has been fantastic compared to my old router.

I don't want the risk of trashing the current router without a replacement ready.

(The current router is a TP-Link router with hardware version "Archer C7 v2 00000000.")

I think Cat-6 or better is more suitable since OP mentioned able to handle 25+ devices simultaneously, assuming OP have a media server, transfer lots of data or heavy gaming running in a same time.
And I agree running on cable as mush as you can because it gives a higher speed compare to WIFI.

Refer to OP questions, check how many core the CPU has (dual is min. nowadays) and how many RAM it has. Some cheap model still offering 128MB ram, which may not suitable for your requirement.
About the house furthest connection problem, if cable can reach and devices use cable only, use a hub instead. If WIFI is a must, check the router you are using can work as a repeater or not. If it can, you can save some money instead of using mesh.
Seriously, I don't know there are models which only manageable by smartphone app...
Personally I prefer a router can stand vertically and has internal antenna, which looks nice and space saving. Somehow it is difficult to find nowadays in my living area...

Newest 'tech' in WiFi is called WiFi 6 (“AX WiFi" or "802.11ax WiFi” ) and 'Mesh WiFi'

Ref. :

https://www.networkworld.com/article/3258807/what-is-80211ax-wi-fi-6-and-what-will-it-mean-for-80211ac.html

https://www.tp-link.com/en/wifi6/

https://en.wikipedia.org/wiki/IEEE_802.11ax

https://en.wikipedia.org/wiki/Wireless_mesh_network

For Suggestions , look at the AX capable of your choice from one of these lists (not all on lists are AX capable) :

https://www.tomsguide.com/best-picks/best-wi-fi-6-routers

https://uk.pcmag.com/wireless-networking/87178/the-best-wi-fi-mesh-network-systems

https://www.cnet.com/news/the-best-mesh-wi-fi-routers-for-2020-eero-orbi-google-nest-netgear/

Otherwise , for cheapest solution choose whatever brand name that you have faith in or will put confidence in.
I do not know what's available in your area of the world and I wouldn't know a WiFi 6 mesh net work if it bit me in the butt anyway...
Also the cheapest possibly is not the best , but sometimes an economic brand may have both knowledge and quality in place !!!

P.S.
Also , last time a friend of mine complained that he had his WiFi drop out on him then it were not the WiFi that were the problem anyway. Problem were that he had put the router next to some other electrical stuff that emitted an electrical field that killed most of the WiFi signal.
My point ? , Money and new tech can take you very far , but common sense is not bad to have either...
(though of course there are problems addressed by WiFi 6 and Mesh , und so weiter , und so weiter, und so weiter)

Anyway, I just updated the firmware on my router, and will see if that fixes the problem.