The Pokemon series has come a long way since the release of Pokemon Red, Blue & Green more than a quarter of a century ago. Much of the innovation found throughout the franchise has come as a direct result of the advances in technology, although that's not to say that there haven't also been some great ideas as well. For all of the new features and functions that have been added to the series over the years though, there are just as many that have fallen by the wayside.

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Plenty of features that were once considered to be staples of the series are no longer present in modern Pokemon titles and there are quite a few that only lasted for a single generation of games. Some of these were likely dropped because they simply didn't add to the games, but there are others whose omissions in later entries in the series made a lot less sense to the fandom.

7 PokeNav Plus

The PokeNav Plus from Pokemon Omega Ruby & Alpha Sapphire

As the mainline series of Pokemon games has developed, so too has the tech that each game's main protagonist carries around with them. While devices like the Pokegear and the Holo Caster each have their benefits though, neither quite lives up to the high standards set by the fantastic PokeNav Plus accessory.

Found in Pokemon Omega Ruby & Alpha Sapphire, this high-tech gadget makes keeping track of everything in the games considerably easier. It reveals the locations of wild Pokemon, reminds players where they've planted berries and even marks the locations of other Pokemon trainers. Although more recent Pokemon games do feature devices with similar functionality, none are anywhere near as well realized as the PokeNav Plus.

6 The Pokewalker

The Pokewalker accessory that was released alongside Pokemon HeartGold & SoulSilver

While the devices found within the Pokemon games are pretty cool, those designed to work in tandem with the titles are arguably a lot more interesting. Starting with the Pokemon Pikachu, Game Freak has released numerous handheld devices over the years, but the pick of the bunch is arguably the Pokewalker.

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Released alongside the 2009 remakes of Pokemon Gold & Silver, this small round device is a little similar to a Tamagotchi, although offers a lot more functionality. It can be used to catch, store or transfer Pokemon and even has a built in pedometer with a selection of enjoyable mini games. Granted, the Pokeball controller offers some of these features too, but the lack of a screen arguably makes it a lot less useful.

5 Trade Evolutions

Trade Evolutions in the Pokemon Series

Since the very first Pokemon games, trading has played an incredibly important role in the series. In every generation, it is an absolute must for anybody hoping to complete their Pokedex, although the way that trading works has changed quite a bit over the past decade or so.

While still important to the series and easier than ever before thanks to the connectivity of modern day consoles, there's perhaps less incentive for people to trade these days than there once was. Trade-based evolutions were fairly common in gen 1, but have become less so with each subsequent release. So much so, in fact, that none of the new Pokemon introduced in the gen 7 or gen 8 games evolve through trading.

4 Secret Bases

Secret Bases in the Pokemon Series

Secret bases were never a huge part of the Pokemon series, but they did offer a nice little distraction for those looking to take a break from breeding and battling Pokemon. Initially, their functionality was fairly limited, although by the time Pokemon Omega Ruby & Alpha Sapphire rolled around they were actually pretty well fleshed out.

As well as granting access to special daily events, secret bases give players not just a place to decorate, but also somewhere they can store their excess items. They can also be visited by other players; either through Street Pass or by sharing a special QR code generated by the Secret PC. Sadly, however, the gen 6 remakes marked the final time that secret bases would appear in a mainline Pokemon game, with Sun & Moon scrapping the concept entirely.

3 Pokeball Seals

A Pokeball Seal from the gen 3 Pokemon games

Pokemon Seals didn't really affect gameplay too much, although they did provide players with more opportunities to customize their playthroughs. These tiny special stickers could be placed on a Ball Capsule around a Pokeball; completing changing the ball-throwing animation as a result.

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Sadly, the feature only appeared in the third generation of Pokemon games along with HeartGold & SoulSilver, although with remakes of Diamond & Pearl on the way, it's entirely possible that seals will be returning soon. Whether or not they stick around for subsequent games, however, remains to be seen.

2 Voice Chat

A Rival battle in Pokemon Diamond & Pearl

There really aren't too many Nintendo Switch games that support voice chat, which is perhaps not too surprising given some of the negatives that often go hand in hand with the function. What may surprise some though is that Pokemon games once included voice chat support, albeit incredibly fleetingly and in a limited capacity.

Diamond & Pearl were the first and only Pokemon titles with built in voice chat, allowing players to communicate during both battles and trades. Granted, this can also be achieved using services like Discord or Nintendo's own Switch Online app, but neither are anywhere near as convenient as a built-in solution.

1 Pokemon Contests

Pokemon Contests

Pokemon Contests are a little divisive among the fanbase; with some loving the idea of Poke-pageantry and others choosing to ignore it entirely. Regardless of one's views on the topic though, it's hard to argue that contests didn't add something extra to the games in which they featured.

Divided into five main categories, Pokemon Contests allow players to compete against other trainers to establish whose Pokemon is coolest, cutest, smartest, toughest or the most beautiful. As well as the kudos, players can also receive special items by competing and even have their Pokemon immortalized on canvas in the Lilycove Museum or Contest Hall if they win.

NEXT: 10 Changes Pokémon Needs To Make For Generation Nine