Whether or not esports can truly work on mobile is a subject of continual debate.
But what's not debatable is that a number of mobile games with a competitive element are now actively targeting this goal.
And interestingly, genre has seemingly little bearing on this. Supercell dabbled first with tournament play in Clash of Clans, before making it a bigger focus in Clash Royale and - one would asume - the soft-launched Brawl Stars.
Then there are RPGs getting in on the act, such as Summoners War and Power Rangers: Legacy Wars, with the more traditional esports genres MOBA and FPS also well-represented.
Tracking grossing performance in an esports context is tricky for two main reasons. The first is that the two are not connected in any consistent way, with thriving tournament-level play not always trickling down to profits from general play.
It's impossible to quantify just how much value is added by esports.
The second is that even if there is a connection between esports and game revenues, it's impossible to quantify just how much value has been added by these tournaments.
So the aim is not to do this, but rather to merely look at how games with esports ambitions are performing in the mobile market as a whole.
First off, are mobile gamers even interested in 'esports'? A rare opportunity to examine this comes in the form of Modern Combat 5 which, on Google Play, changed its subtitle from Blackout to eSports FPS on November 26th 2016.
In December that year, Gameloft backed that name change by partnering with leading esports organisation ESL. It also added features to encourage competitive play, including better matchmaking, custom lobbies and five-versus-five tournaments weekly and monthly to compete for cash prizes.
However, this was not enough to arrest the decline of a game that launched way back in 2014. When the name was changed to include its new esports focus, Modern Combat 5 ranked 317th in the Google Play's US grossing charts.
Just over a year later - November 30th 2017, when it sat at 501st - was the last time it even registered on the top grossing charts. Of course this is hardly unusual for an ageing game, and could be down to many factors, but it hardly points to a successful esports rebrand for the title.
One company that cannot be accused of being a Johnny-come-lately to the mobile esports space is Super Evil Megacorp, whose mobile MOBA Vainglory has been primed to be an esport from the off.
Vainglory's trailblazing has meant facing serious barriers.
Its trajectory has been the closest to its PC counterparts - slowly building a community before gaining recognition from the esports establishment - of any mobile game. And of course, its trailblazing has meant facing down serious barriers.
The result is that the game's grossing performance - 429th in the US iPhone grossing charts as of December 11th, and generally bobbing between the mid and late-hundreds - is largely academic. Its team has another focus, which remains unchanged.
However, as in the case of Modern Combat 5, esports is increasingly becoming a target for pre-established games. This is a different proposition altogether, with the companies behind these games essentially fighting on two very different fronts.
And it can be difficult to contest both with the same vigour.
Summoning an esport
A recent example of this would be Summoners War. The RPG had been successful for years, a frequent top grosser, when Com2uS facilitated cross-regional PvP in March 2017 with the launch of its World Arena.
This enabled a new esports focus, headlined by the World Arena Championship. Com2uS point to this as a success in its recent financials, but its positions in the US iPhone grossing charts have only become more inconsistent since the introduction of the World Arena.
Another mobile game that is now increasing focus on esports is World of Tanks Blitz. No doubt helped by its experiences of esports on the PC side, Wargaming tripled the prize pool for 2017's Twister Cup to $30,000.
The Twister Cup finals were held on 1st October, but seem to have little impact on World of Tanks Blitz's US iPhone grossing chart position.
On the same day, the game hit 360th - a reflection of where the game now finds itself, its best grossing years 2015 and 2016 now behind it.
Clash Royale is a different story, being designed from the off for synchronous PvP. Features like TV Royale also showed that Supercell took spectator into consideration.
But the inaugrual North American championship, Supercell's first official competitive event, didn't come along until October 21st 2016. From then until November 17th, up to 120,000 players each week could enter daily qualifiers to progress in the tournament.
This was a strong grossing period for Clash Royale, in which the game never dropped below fourth in the US iPhone grossing charts and spent 15 out of 28 days at its summit.
But even before that, Supercell dabbled in tournament play with Clash of Clans. And for the release of its major Builder Base update this year, which added direct head-to-head battles, it ran a tournament between YouTubers.
At the time of writing, the stream of tournament has more than 6.25 million views on YouTube.
Declining games can't ride the esports hype and find their success instantly renewed.
The builder base update was a huge success, with Clash of Clans enjoying a nine-day spell atop the US iPhone grossing charts immediately after its release.
The 'e' does not stand for 'easy'
It's difficult to draw a definitive conclusion to this, other than what should be obvious: that declining games can't ride the esports hype and find their success instantly renewed.
And as esports only really caters to a very particular subset of invested players, it's hard to see any real grossing impact - at least in the short term.
But really, there are two approaches on display here. The one exemplified by Vainglory is to truly establish itself on the esports circuit, and then go from there. The other, very much Supercell's strategy, is to adopt esports elements in community-building and marketing.
Both are equally valid, but there are equally a number of ways in which either approach can fall flat.