My Samsung S8 has given up the ghost, and the prohibitive cost of repair means I’m in the market for a new mobile phone. I’ve come up with a wishlist of specifications. Are there any phones due in the coming months that offer all of these? I don’t believe anything currently on the market does. Declan

There are four obvious problems with having a list of specifications for the device you want to buy, whether it’s a smartphone, tablet, laptop, digital camera or whatever. The first and biggest problem is that it can easily eliminate most of the products on the market or, in your case, all of them. In fact, it’s a problem I share: nobody offers a laptop that meets my most-desired specification, though a few come close.

The second problem is that it can be hard work. There are thousands of products with variable specifications, many of them incomplete. The numbers you can find may well be a mixture of inches and centimetres, kilograms and pounds, and binary and decimal bytes. In some cases, I’ve created spreadsheets to compare products, partly to automate the format conversions.

The third problem is that choosing purely on specification ignores other important features, such as manufacturing quality, ergonomics, software experience, reliability and support. That’s why it’s a good idea to get a “hands on” and to read independent reviews, plus the manufacturer’s support forums, if any.

There’s always a risk factor, and some technology buyers are more risk-averse than others. Some are happy buying smartphones from little-known suppliers on Chinese websites; others will prefer to buy from a local shop, so they can take it back when they run into a problem.

The fourth problem is that most of us have personal preferences. Some people have historical reasons for choosing a particular brand – they’ve had good or bad experiences with other products from the same company – or they think it has more social credibility. Maybe they just like the colour or the way it looks. Buyers are often willing to compromise on specifications when less tangible aspects of desirability trigger an emotional response.

I’m not saying that buying using specifications is wrong: people who ignore them risk buying stupid things. However, specs are not the whole story, and for many buyers, they are not even the main story. Either way, knowing what you value will help you make a more informed choice.

Smartphone specs

Google’s Pixel 4 XL has a 90Hz screen, but only 6GB of memory and no expandable storage. Photograph: Samuel Gibbs/The Guardian

From your wishlist of specifications, you want to buy a dual-sim Android 10 smartphone with at least 8GB of memory, 128GB or more storage (expandable), and a 90Hz or better display. This sort of spec should give you a decent range of options. Unfortunately, you also want a headphone jack, wireless charging and water resistance, which reduces the options to none. The last thing on your wishlist is 5G: “nice to have for future proofing; not required”. That’s a nice thought, but “Android” and “future proofing” are mutually incompatible.

I don’t know of any phones that exactly match your wishlist, and I think the long-term trend is the other way. I envisage future smartphones as completely sealed devices with no ports at all. Sims will be “virtual” esims (stored on the device, instead of physically inserted) and everything else will be done wirelessly.

Headphones are on the way out, and microSD card slots – used to add storage – will probably go the same way. For now, your spec is mostly practical if you can fit a microSD card into a hybrid sim slot, instead of a second sim.

Possible options

The OnePlus 7 Pro was one of the first phones available with a 90Hz screen, and shipped in a 5G variant. Photograph: Samuel Gibbs/The Guardian

It only took a couple of minutes on GSM Arena’s Phone Finder to come up with what might be your best choice – the Xiaomi Redmi K30 – but you could also consider the Lenovo Z6 running Android 9. If you want a 5G phone, the only option is the Xiaomi Redmi K30 5G. You can compare all three here. They are all reasonably priced.

These mid-range smartphones have the features you want except for wireless charging and the real stumbling block, water resistance. However, you can get both of those from your current supplier in the form of the Samsung Galaxy Note 9, S10, S10+ and S10e. If you can find dual-sim models with Android 10, the only thing you’d be giving up is the high screen refresh rate, and the rumour is that Samsung will address that in February.

On the whole, then, I think you should stick with Samsung, unless you have totally gone off the company, which would be understandable in the circumstances.

Choosing other devices

Laptops come in so many different sizes, form factors, capabilities, age, operating systems and prices, filtering by specs can be useful in narrowing down the options. Photograph: Bebeto Matthews/AP

GSM Arena is really useful if you’re buying a smartphone or a tablet – the two product categories it covers. If I’m buying something else, I’m often tempted to ask “what’s the GSM Arena of” cameras or laptops or TV sets or whatever. There is rarely a good answer, but for digital camera buyers, the Amazon-owned DP Review website is excellent.

Like GSM Arena, DP Review lets you find cameras by their specifications and compare them side by side. I’ve used these features in earlier answers about digital photography.

Laptop buyers could really do with their own GSM Arena, but I’ve never found one. However, the advanced search feature on the somewhat obscure noteb.com is worth a go. It has sliders to set maximum and minimum values for things like launch date, number of processor cores, power consumption, memory, storage, display size and vertical resolution, battery capacity, estimated battery life, and so on. You can ignore any fields you don’t care about. You can sort the results by value, price, performance or by name, and its rankings seem sensible. Alternatively, you can focus on a particular class of laptop – the options are Mainstream, Ultraportable, Business, Gaming and CAD/3D modelling – or on a single brand. Clicking on a laptop brings up its full specification.

This “laptop search engine” also has a blog and a YouTube channel. It looks like a labour of love. It solicits donations and has a Patreon page. One incentive is that donors can get personal laptop buying advice. I hope it survives. Maybe Jeff Bezos should buy it, because Amazon’s laptop search badly needs upgrading.

There are, of course, plenty of useful websites such as Laptopmag, Notebookcheck and the Wirecutter. They all have good reviews and top product picks. However, when it comes to finding laptops that fit a choice of specs, I usually end up using the limited and often clunky filtering features on retail sites such as Currys PC World, eBuyer, Argos, Laptops Direct and so on. The obvious drawback is that they won’t find interesting products that they don’t stock. And those are the ones that someone hunting for a very particular spec may well want to buy.

A warning note

GSM Arena is a global website, so some phones may not work in the UK, or wherever you happen to live. There’s less of a risk now the UK has six different 4G bands between 800MHz (the old analogue TV band) and 2.6GHz, but if you’re buying a smartphone from overseas, it’s important to check. Phones sold within the UK should, of course, work with British networks.

Have you got a question? Email it to Ask.Jack@theguardian.com