In this presentation, we will examine the performance status of thin-film transistors on flexible substrates, and contrast it to the requirements for future soft electronics in IoT and healthcare. Electronic systems comprise different blocks, with different requirements. We will specifically examine the design blocks needed for a number of specific applications. The first application that we consider is tags for wireless communication (RFID, NFC). We discuss performance achievable with unipolar organic transistors, complementary organic TFTs, oxide TFTs, and complementary hybrid organic-oxide TFTs. We also propose a vision on future applications. The second application that we consider are sensor tags. In addition to the wireless communication block, they also need analog-to-digital converter. We again review the currently achievable performance of such block with TFTs on plastic. Finally, we briefly discuss other components, such as a re-programmable non-volatile memory.