Apple’s increasing tendency to develop core iPhone components inhouse has caused significant problems for many of its current or former suppliers, but the issue is not confined to the iDevice maker. There is a general move, by major handset vendors, to assert control over pricing and availability in their supply chains, and bring key components inhouse. Samsung and Huawei already have their own processors and modems, and Samsung is reportedly developing a GPU (graphical processing unit) for its smartphones. All this reduces the addressable market for component specialists and makes them reliant on more cost-sensitive handset makers which lack the inhouse development resources of the big three. These will demand similar levels of performance for lower cost, and shift the…