Very few mobile games bother with using the accelerometer anymore, generally just racing games using it for steering, by all means point out any modern mobile game out right now that focuses on or even widely uses the accelerometer for play, other than console ports like thomas was alone, which only have accelerometer support because of the vita, a console which in itself is failing miserably.

It became unpopular in mobile too, around about the same time the Wii did.

THIS. Ninty doesnt push the Wiimote at all despite it being completly compatible with Wii u. MS just dropped Kinect. Sony didnt even really seem to bother with Move. Motion is back to being niche and IMHO thats teh way it should be

Also, an accelerometer barely qualifies for (and i would argue, doesn't qualify) as motion controls, and instead is just a bidirectional analog input, there is no external tracking (lightbar / kinect / eyetoy-or-pseye) tracking positioning, so the accelerometer input can be used with nothing but gravitational shift (try playing a mobile game that uses accelerometer in a car while its turning).

Body movement tracking (true motion control) was a fad, Sony got there as the Wii trend was tapering off, and sold poorly, Microsoft got there with Kinect around the same time, and sold decently, but only because Microsoft broke out the credit card and advertised / pushed so hard to force a moderate success.

Accurate motion control was a fad
Cheap motion control (mobile) was a fad

Lol soundwave do you make these threads just to troll Nintendo fans?

Catching a commuter train in 2014, it's very common to see people tilting their phone as they play stuff like endless run racers, Graviturn and similar tilt-based puzzlers, even Pacman. 3DS also uses motion, and unlike Vita, it's not a failure.

If it was really dead, phones would have stopped incorporated accelerometers; they could cut build  cost by removing an unused feature.

I once found a Nes and like 8 games in the trash. Thank you!

TRUE, at least until it (motion) becomes A LOT more than just waggle this and that.  Zelda SS was a great use of the Wiimote that actually mattered in gamplay.  Unfortunately, most games did not do it right and many games did not need motion at all to your point.

I think motion VR would be amazing, but we might be many years off. 

There is also a Xbox One behind it!
Oh, wait...
That is a old VCR...

you seem to keep missing the point or just ignoring it. No one said anything about life cycles. They are talking HOW it sold in that time. It went from being on track to having a more than 50% market share to about 35%. Lets say its not a fad. Fine, but there is nothing normal about a consoel on track to sell more than PS2(some were even saying ti could sell 200mil) to not even able to match the PS1. That is odd no matter how one spins it.

Some people still play Wii, some people still play PSMove, and some Kinect, it does not mean it was not a fad.
Hell, panling was a fad but there are people still doing it, mood rings were a fad and some people still wear them.

The games you listed, here are the install stats.
Graviturn  - 100,000 - 500,000

Install stats for games that only use touchscreen. (android since ios dont list installs)
Line POP - 10,000,000 - 50,000,000
Line Pokopang - 10,000,000 - 50,000,000
Candy Crush Saga  - 100,000,000 - 500,000,000

Endless run racers: The only popular ones actually use swipe and not the accelerometer, Temple run 1 and 2, use swipe, the popularity of games that use tilt sensor are significantly lower than the games that dont, and this can be confirmed by simple searches and browsing the highest rated and highest installed games lists.

Accelerometers are included simply because removing them would prevent the few users that actually want to play this games, and from people that use the tilt sensor in other applications like health tracking and mapping, from doing so, and no mobile phone manufacturer is going to remove features having MORE features is the ammunition needed to compete in the mobile hardware market today.

Again, motion controls is a fad.