Right, we made the choice to lower the price of the Picollo DAC so that people could make the choice just based on the style of amp and features. The cost of production is a little more with the PDAC, but that's OK. The PDAC of course has a 16/48 bit DAC and is an integrated amp/DAC. It should work natively, without an app, on many android devices. It works with PC's and Mac's without a software driver. So no muss no fuss. Most audio tracks are 16/44.1 so most customers will be served by this amp/DAC. Higher res tracks will be downsampled, but the availability of higher res tracks is still developing. The Picollo amp takes a different approach to amplification, using hand matched silicon triodes. This produces a warmer tube like sound. These cannot be used with a DAC for stability reasons, so that's why two designs.