I'd argue for a management, design or testing roll specialising in "mobile development" is fine, even a benefit. But for developers it makes no sense, an avera

I'd argue for a management, design or testing roll specialising in "mobile development" is fine, even a benefit. But for developers it makes no sense, an average Android developer makes a terrible iOS developer and vice versa. A 100% iOS dev is going to be 50% better (at least) than one that splits their time between 2 (or 3) platforms.