I notice you're asking for a "detailed story" about the — but I must clarify that no such phone model exists in Sony Ericsson’s official lineup. The closest models are the W100i (Yendo) or the W150 (which was never released under that exact name). The W100i was a full-touch Walkman phone from 2010, but firmware stories for actual models involve technical details, update logs, and regional variants.
Which would you prefer?
If you’d like, I can instead write a about a fictional Sony Ericsson W150i — including its firmware development, bugs, hacking scene, and a dramatic update failure — or I can provide a real, accurate technical history of the W100i firmware (the closest real model). Sony Ericsson W150i Firmware