In its most recent update — which should be on the App Store no later than September 12th, if not already — Pokémon GO added its "buddy system" which lets you set a Pokémon as your buddy and earn that Pokémon's candy for walking.
However, given Pokémon GO's recent drop in users, we can only wonder if the buddy system is enough of an update to keep players interested.
For Starters, The Game's Tracking Could Still Use Some Improvement
Anyone who's had the pleasure of trying to hatch Eggs in Pokémon GO will likely not be surprised by this, but it's still a major limitation of the game. If you want to earn candy by walking with your buddy, you have to have your phone open. This wouldn't be quite as big a deal if the upcoming Pokémon GO Plus wearable could track movement, but, sadly, it doesn't.
UPDATE 09/14/16: The Plus wearable will track movement, it turns out.
But perhaps an even bigger issue is the game's tracking system itself, which still... well, it could be improved. Rarely does the game actually track kilometers traveled entirely accurately. No, it's not terrible, but it's still frustrating at times to see that you've "walked" half of what you've actually walked.
And speaking of walking, it's still a bit frustrating that the game's speed limit for detecting movement is so low. Yes, it's a necessary evil to prevent players from gaming the system and gaining crazy amounts of kilometers just by driving, but it would still be nice if going for a bike ride contributed in some way to your movement.
I remember the first time I went out for a leisurely bike ride expecting to hatch some eggs, I was severely disappointed to find out that I had apparently been moving too fast for the game to count my movement. I mean, it was an enjoyable bike ride. But still.
Even If Tracking Is Improved, There Are More Features Players Want To See Added
The buddy system is a great system, don't get me wrong. It fixes one of the game's major problems of not being able to evolve some of the game's more rare Pokémon. After all, some of the most fun in the handheld Pokémon games is finding that rare Pokémon and battling with it until it evolves.
Speaking of which, the game doesn't have battling or trading yet. The buddy system helps you more easily evolve Pokémon you already have, but if you're after a Pokémon that your friend happens to have two of, well, you're still out of luck. Wouldn't you be more inclined to play and converse with other players if you knew there was the potential of trading for That One Pokémon that you could never manage to find?
Or, back to the original point, wouldn't it be fun to show off your roster (and potentially earn candy!) by battling those other trainers? Gym battles are a unique challenge, but not the same as running into another trainer, flipping your hat backwards, and throwing out your Pokémon of choice to battle.
But Still, Longevity Ultimately Relies On Giving Players Reasons To Play Regularly
Forgive me if this sounds like a bit of a stretch — I promise it's gonna make sense. The latest World of Warcraft expansion is another evolution of the max-level questing system that Blizzard has worked to refine over the years.
Rather than offering daily quests (thus, wearing out players by making them feel like logging in daily is a necessity to keep up) or no quests at all (which winds up giving no reason to log in), Blizzard has implemented world quests, which appear randomly, can last for several days, and offer solid rewards that help but never feel absolutely required. You're rewarded for playing, but not playing doesn't feel punishing.
This is the sort of system Pokémon GO needs.
Maybe there's a bonus event that rewards you with XP or Razz Berries for stopping at PokéStops a certain number of times per week. Or maybe your buddy can get bonus candy for more than walking — say, every 5 Pokémon you catch per day while you have a buddy will earn you more. Heck, maybe at the end of every Pokémon encounter there could be a random chance to gain several bonus candies, XP, or some other items.
Whatever the system, Niantic's buddy system is a step in the right direction — with room for improvement. Small, but regularly obtainable rewards will keep players coming back. The trick is to reward players just for playing the game.