▁v 1 . 2 5 ▁was ▁released ▁by ▁an ▁Italian ▁developer . ▁Mod ded ▁firm ware ▁releases ▁v 2 . 1 0 ▁and ▁v 2 . 2 0 ▁came ▁out ▁later . ▁Comp ared ▁to ▁the ▁official ▁firm ware ▁v 1 . 2 5 , ▁they ▁add ▁a ▁" Sa fe ▁Mode " ▁( the ▁device ▁can ▁be ▁connected ▁to ▁the ▁computer ▁even ▁when ▁br icked ), ▁a ▁DR K ▁( Device ▁Res cue ▁Kit ) ▁to ▁un br ick ▁the ▁device , ▁a ▁CPU ▁down clock ing ▁tool ▁to ▁save ▁battery ▁life ▁and ▁the ▁possibility ▁to ▁custom ize ▁the ▁resources ▁( p ictures , ▁sounds , ▁fonts , ▁language ) ▁of ▁the ▁firm ware . ▁ ▁Since ▁ 2 0 1 1 ▁the ▁alternative ▁free ▁and ▁open - source ▁firm ware ▁Rock box ▁can ▁be ▁installed ▁on ▁the ▁Y P - R 0 . ▁Un like ▁most ▁usual ▁Rock box ▁targets , ▁the ▁Y P - R 0 ▁port ▁is ▁not ▁a ▁native ▁port . ▁It ▁runs ▁as ▁an ▁application ▁based ▁on ▁the ▁original ▁Linux ▁kernel ▁used ▁by ▁S amsung ▁in ▁the ▁official ▁firm ware . ▁That ▁makes ▁the ▁development ▁easier ▁but ▁on ▁the ▁down side , ▁Rock box ▁bo ots ▁up ▁slower ▁as ▁on ▁the ▁other ▁usual ▁targets . ▁As ▁of ▁December ▁ 2 0 1 3 , ▁the ▁Y P - R 0 ▁is ▁an ▁un stable ▁port ▁according ▁to ▁the ▁official ▁Rock box ▁classification . ▁In ▁fact , ▁it ▁runs ▁well ▁enough ▁for ▁a ▁daily ▁use ▁but ▁cannot ▁be