Back when E3 2015 rolled into town, we remarked that AAA developers and publishers just don't get mobile.

The few smartphone-based games on display were pretty much all collectable card games (CCGs) based on popular franchises that had never had anything to do with cards in the first place.

However, there was an exception: Fallout Shelter - a game that worked with the Fallout lore, and worked perfectly on mobile.

Making a great mobile game, after all, isn't just about porting a console game to mobile, giving it icky virtual controls, and watching the money come rolling in.

So let's take a look at how the other big AAA franchises can learn from Bethesda's game and truly take advantage of the platform to create another mobile gem.

Assassin's Creed

Assassin's Creed is all about stealthy assassinations, swashbuckling combat, ship or mounted battling, and a dash of contract management on the side.

So let's take the stealth sections of Republique, the combat of Infinity Blade, and the strategy management of Clash of Clans, then give them an Assassin's Creed polish. Bob's-your-uncle you have a serious mobile game on your hands.

You could even throw in the ship combat from Assassin's Creed Pirates and/or some Rival Knights-esque mounted combat to really shake things up.

Gears of War

If done right, cover-centric shooters can really work on mobile, as the problem of trying to move and shoot at the same time is eliminated.

Gears of War could lead the charge here, taking the excellent touch control scheme of Dead Space mobile and the cover mechanics of Overkill 3 before injecting the oh-so-satisfying blasting of Gears of War.

Batman: Arkham

Batman: Arkham Asylum had an unrivaled combat system, brilliant characterisation, and a small area to explore, Metroidvania-style.

Going the 3D route on mobile would be problematic - likely due to a reliance on virtual controls. Instead, let's imagine a 2D platformer approach similar to Arkham Origins Blackgate but with the touch controls of Limbo, the swipey combat of Combo Crew, and the structure of Traps n' Gemstones.

Let's just do the right thing and leave out the Batmobile entirely. Am I right?

Call of Duty

First person shooters haven't been particularly great on mobile but the potential is definitely there as Midnight Star can attest.

So let's take the on-rails shooting of Midnight Star, sprinkle in a steady stream of explosve set pieces, and take inspiration from Telltale's The Walking Dead during Call of Duty's more cinematic moments.

Resident Evil

Survival horror has already had a rebirth on mobile but it's only right that one of the genre's first and finest gets well-represented on the platform.

Forgotten Memories provides a good framework for third person survival horroring but Five Nights at Freddy's is where Capcom should look for jump-scare inspiration - it's got that in abundance.

It would be silly to ignore the flourishing survival genre so look at Minecraft or Terraria to build a true 'digging in' system. Imagine that Resident Evil 4 survival section with Luis Sera but in a house you built and set over a larger period of time?

Stop me before I start talking about tower defence.

Metal Gear Solid

If Metal Gear Solid were to come to mobile, it should definitely return to its roots.

And what better inspiration do we have for some isometric stealth-based gameplay than Hitman GO. It doesn't have to be turn-based either.

The characters could move independently of you and you simply choose the opportune moment and place to attack from.

The Witcher

This could be as easy as a port. The first Witcher had a mouse-only control scheme that could easily be adapted to touch.

Heroes Call had a very similar touch-based movement and combat system on mobile and it worked like a treat. The success of Baldur's Gate, Icewind Dale, and Shadowrun on mobile demonstrates the hunger for good western RPGs on the platform.

Rainbow Six

The recently released Door Kickers was, essentially, a very simplistic Rainbow Six on mobile.

Throw in some fancy visuals, the tools of the trade, and a convoluted plot and you have Rainbow Six on mobile. It's as easy as that.

Want more? Check out our growing collection of Fallout Shelter features!