Conventional biomedical devices are rigid or bulky, making generally impossible to apply directly to human issues and real-time biosensing. To enable direct application to human tissue and real-time biosensing, platforms with characteristics such as small size, flexibility, stretchability, or biodegradability are necessary. Here, we are developing next-generation biosensing/bioelectronic platforms including wearable, implantable, wireless, or neural probe devices with aforementioned characteristics using various methods such as nanofabrication.