A variety of haptic improvements useful in mobile devices are detailed. In one, a smartphone captures image data from a physical object, and discerns an object identifier from the imagery (e.g., using watermark, barcode, or fingerprint techniques). This identifier is sent to a remote data structure, which returns data defining a distinct haptic signature associated with that object. This smartphone then renders this haptic signal to the user. (Related embodiments identify the object using other means, such as location, or NFC chip.) In another arrangement, haptic feedback signals social network information about a product or place (e.g., the user's social network friends “Like” a particular brand of beverage). In yet another arrangement, the experience of watching a movie on a television screen is augmented by tactile effects issued by a tablet computer on the viewer's lap. In still another arrangement, commercial vendors bid for rights to employ different ones of a library of haptic signals on one or more users' smartphones, e.g., to alert such user(s) to their products/services. A great variety of other features and arrangements are also detailed.