I was unable to justify the added cost of a smartphone plan, and didn't expect the price to get down to a reasonable range for several more years, if ever. But I recently found that Virgin Mobile US offers unlimited data/text and 300 minutes of voice for $25/mo, without being tied to a contract. This is a much better deal than anything else I've found in the US (it's less than what many of my friends pay for their dumbphone contract), and was enough to finally bring me into the smartphone world. They have two Android phones right now - the Intercept and the newly-released Optimus V. Neither one is a top-of-the-line phone, but the Optimus is particularly impressive for the price.
I think it's unlikely that Perl is being used for any of the heavy computations. I would guess that Perl is being used as a glue language that interfaces with the database and programs written in lower-level languages to do the heavy lifting.