The article presents the development of ultraflexible and conformable polymer light-emitting diodes (PLEDs) and organic photodetectors (OPDs) for creating optoelectronic skins (oe-skins). These devices, with a total thickness of only 3 μm, are designed to be worn on the human skin, integrating multiple electronic functionalities such as sensing and displays. The PLEDs and OPDs are fabricated on thin polymeric films, reducing their thickness and improving their flexibility. The devices exhibit high performance, with external quantum efficiencies (EQEs) and luminances comparable to those on glass substrates. The passivation layer, consisting of alternating inorganic (SiON) and organic (Parylene) layers, ensures air stability and minimizes water vapor transmission rates. The combination of these devices allows for the creation of a reflective pulse oximeter, which can measure blood oxygen levels non-invasively. The system also includes seven-segment digital displays and color indicators, enabling visual data presentation directly on the body. The ultraflexibility and conformability of the devices make them suitable for various biomedical applications, such as monitoring vital signs and enhancing human abilities.The article presents the development of ultraflexible and conformable polymer light-emitting diodes (PLEDs) and organic photodetectors (OPDs) for creating optoelectronic skins (oe-skins). These devices, with a total thickness of only 3 μm, are designed to be worn on the human skin, integrating multiple electronic functionalities such as sensing and displays. The PLEDs and OPDs are fabricated on thin polymeric films, reducing their thickness and improving their flexibility. The devices exhibit high performance, with external quantum efficiencies (EQEs) and luminances comparable to those on glass substrates. The passivation layer, consisting of alternating inorganic (SiON) and organic (Parylene) layers, ensures air stability and minimizes water vapor transmission rates. The combination of these devices allows for the creation of a reflective pulse oximeter, which can measure blood oxygen levels non-invasively. The system also includes seven-segment digital displays and color indicators, enabling visual data presentation directly on the body. The ultraflexibility and conformability of the devices make them suitable for various biomedical applications, such as monitoring vital signs and enhancing human abilities.