When not building phones (like the Krave ZN4 or the AURA), Motorola tries and succeeds to make various other products, like GPS navigation systems. The latest such products are MOTONAV TN20 and MOTONAV TN30, both of which were officially announced just few hours ago. Released in the US exclusively via RadioShack, Motorola’s new GPS are available right away, retailing at $199.99 (the TN20) and $299.99 (the TN30). The first GPS navigation system, MOTONAV TN20 measures 3.7 x 3.2 x 0.7 inch