Hi all, I don’t post much but hope you don’t mind my thoughts on this.
Jonagold, and in fact all apples need different varieties nearby to have successful pollination. Being a triploid (like Bramley), it must have two other varieties nearby in order to have chance of setting fruit. If your neighbours have fruit trees, even (and especially) flowering crabs, they may do the job. It is however susceptible to a few maladies, which home gardeners may struggle to fend off. There are dozens of good varieties around and I would advise tasting a few local ones, and ask around about disease resistance before making a long term decision on what trees to buy. It can vary dramatically depending on your local climate. Some will tolerate wetter climates, some prefer drier climates, colder and warmer…eg. Cox and Discovery prefer warm and dry, as does Nonpareil, Cornish Aromatic doesn’t mind damp as it comes from the West Country. Some varieties grow healthily and are a good choice for organic methods, and if you give them their preferred conditions you are getting off to a good start.
Reine des Reinettes, as mentioned is a delicious fruit, and is the one traditionally used in tarte tatin as it keeps its shape when cooked.
I would definitely avoid the multi grafted trees, they are a novelty but unless all the varieties used have the same growth rate, they tend to fail.
The Croquers de Pommes https://croqueurs-national.fr may be useful in hoping you decide, as they have regional groups with knowledge on local varieties.
Hope this helps a little,