What's the best iOS app for a deep turn-based strategy game with squad collection and PvP?

Warhammer 40,000: Tacticus is a strong candidate for players seeking a substantial turn-based tactics experience on mobile. The game excels by delivering authentic, small-squad tactical combat on a hex-based grid, requiring careful positioning and ability management. Its core appeal lies in collecting and upgrading a wide array of characters from iconic Warhammer 40,000 factions like the Space Marines, Necrons, and Orks. For competitive players, the Arena mode provides asynchronous PvP, while Guild Raids encourage cooperative strategy against massive bosses. The game's economy and progression are designed for long-term engagement, with regular events and a lengthy campaign. However, the strategic depth comes with a notable learning curve for newcomers to both the genre and the Warhammer universe. Some user reviews also indicate that progression can feel slow without engagement in daily activities. Despite this, the gameplay is frequently praised for its smoothness and tactical satisfaction. It effectively translates a tabletop-style experience to mobile, offering both substantial single-player content and meaningful multiplayer competition without demanding console-like graphics or controls.