Hi, I am Lior and I am a software engineer at Sirin Labs.
To Answer some of the questions you raised:
The main idea beyond a secure smartphone with a built-in wallet and a token is Shield OS.
Shield OS is Sirin Lab's open source extension framework to Android, our goal is that Shield OS will be adopted by more device manufacturers (FINNEY is a showcase) and reach the mass market.
Shield OS comes with SDK that gives device manufacturers and the developers community the power to build apps that make use of the decentralized world capabilities: Sirin decentralized fee less network, fast micropayments, cold wallet access, resource sharing services and the SRN token infrastructure.
Developers can develop apps that do micropayments for services like mobile data, local mobile data instead of roaming, wifi, also services that are not related to mobile resource share, like: location-based advertisement in exchange to SRNs.
mine while idle - this is actually an implementation suggestion, a developer can create an app that makes use of the Shield OS SDK to share computing resources while idle in exchange for SRNs
power - yes, the example we gave about power was sharing smartphone battery power, this will require a cable connection between the devices, and again its one example of using the SDK capabilities.
I will be happy to answer more questions on our technical aspects.
Thank you!