PC, console, or mobile: how to choose the best way to play
The network's three games run on more than one platform, so the question isn't just "which game to play," but also "where to play it."
Mobile
Wins on practicality: you already have the device, you can play anywhere, and it's Free Fire's native format (Android 4.4+ or iOS 9.0+, runs with just 1GB of RAM). The downside is the small screen and touch controls, which are more of a drawback in games with precise aiming like Fortnite.
PC
Wins on precision (mouse and keyboard) and graphical capability — it's where Roblox and Fortnite show their full visual potential. Fortnite recommends a GTX 1060 or higher with 16GB RAM to run well; Roblox is much lighter, running even on integrated graphics cards with DirectX 10.
Console
Sits in the middle: more powerful than most phones, simpler to set up than a PC (no worrying about drivers or varying minimum requirements), but with the cost of the console itself and, in some cases, online subscriptions to play multiplayer. Fortnite and Roblox are available on PlayStation and Xbox.
There's no single right answer — it depends on what you already have on hand and how much time/money makes sense to invest. The full minimum requirements for each platform are on each game's page.