Does anyone have graphic design advice for designing for a product across different platforms? I know from a UX perspective, it's important to take into consideration the different ways people interact with products on a specific platform and then applying it to your product.
This also goes for design, but at times I see products lacking consistency in design (Android will look completely different from iOS) at the expense of maintaining consistency with the platform they are being served on. For example, Google recently released Material Design so it makes sense to apply those design practices to your product to be consistent with the platform. At the same time though, if you have the same product/application being served on Apple products, it does not make sense to apply those practices necessarily because it does not fit with the platform.
So my main question which I can probably ask more clearly here: Should we be designing products to be consistent with the platform even if it is at the expense of consistency with the product? When, if ever, is it appropriate and when, if ever, is it not?