We propose a design and optimization methodology for high performance and ultra low power digital applications on flexible substrate using low temperature polycrystalline silicon thin film transistor (LTPS TFT). We show that by using ultra-thin bodies and minimizing the mid-gap trap density by hydrogenation, LTPS TFTs (in 200 nm technology) can achieve higher performance than standard TFTs. We also demonstrate that it can be a promising candidate for both sub-threshold and super-threshold operation with performances comparable to contemporary bulk silicon. However, due to grain boundaries (GBs), there can be large intrinsic variations in such devices. Hence, there is a need for GB-tolerant design. Integration of proposed digital electronics in conjunction with conventional display application of LTPS TFTs on flexible substrates (system-on-panel) will open up plethora of new and interesting applications.