Device, system, and method of selective activation and configuration of components. A manufactured electronic device includes at least one hardware component which is locked or disabled or deactivated, or is feature-constrained. An end-user of the electronic device utilizes a computerized platform or a cloud-based platform to request activation or upgrade of that hardware component, optionally together with paying a fee for such request. In response to the request, an access token is generated by the manufacturer of the electronic device, with cryptographic elements that indicate to the electronic device that the request is approved and authorized by the manufacturer and also by the relevant vendor or communications carrier. The electronic device validates the access token, and modifies configurational parameters in its secure storage to activate or to upgrade the capabilities of the relevant hardware components of the electronic device.