This question obviously depends on how much time you're going to spend playing the game, and what game you're talking about. I saw Call of Duty Advanced Warfare in a shop the other day and I thought the game was expensive but worth it. When I look at mobile games it's a different matter. Most...
I spend 5-6 hours on my laptop on average. Although I really enjoy using it, I could probably survive without it. However, I now find it very difficult to survive a day without using a smartphone. When I forget my phone, it's really inconvenient.
I currently use an Android phone with a 5 inch screen. It's ok for gaming, and I can run Fifa 15 on it with occasional lag. Unfortunately it doesn't have front facing speakers like your HTC One, so sound isn't great. Running Bloons TD5 is probably a very good benchmark test.
Minecraft does get boring, as do all games, but 'modded' Minecraft does make the game a lot more interesting. Yes, the Minecraft hype seems to be over, but the game was and still is very successful. I mean, Notch just got himself a huge mansion.
I tried Clash of Clans, but I never really got into it. It's a 'freemium' game that is too time consuming and not very user friendly when played on a small mobile phone. I do play other strategy games on the internet using my laptop.
I love their Youtube advertisements though.