The need for easily accessible biologic-based diagnostics tests has been more than established with the recent advent of PCR-based diagnostics and the soon-emerging isothermal diagnostics for detecting SARS-CoV-2 virus. In this project, a prototype miniature biological thermal cycler for isothermal and PCR reactions that satisfies these key value points was designed and constructed. The device is built to function within the plug-and-play compatibility with iAssay’s cloud-connected, point-of-care diagnostic ecosystem. This means that it fits within the modular test cartridges that function with the iAssay portable diagnostic system. To accomplish this, the prototype device is faced with strict spatial and power restrictions that limit its size 50.8mm X 127.0mm X 50.8mm (2” X 5” X 2”) and an operating power of merely 4 Watts, as the device draws power and transfers data through a 5V, 800 mA USB-3.1 connector. Yet still, the thermocycler module is able to cycle 50 microliters of fluid held within a standardized 100 microliter PCR tube at a ramp rate above 0.5 °C/sec within a temperature range from ambient to 95 °C. The fluid heating stage makes use of an optimized copper 145 heat block that is heated via a power resistor, while the cooling stage dissipates heat quickly through a combination of a fan and a Peltier chip module. The power input of each of the heating and cooling components is managed by an Arduino control algorithm using MOSFET switch circuits.