We characterized a novel Atmospheric-Pressure-Interface Time-of-Flight (TOF) Mass Spectrometer. By accumulating ions in a trap prior the TOF mass analyzer, we achieve a limit of detection in the 10^-3 to 10^-6 ppq range with temporal resolutions in the order of 1 s to 10 min, respectively. This makes it highly relevant for atmospheric measurements, as it enables probing short-lived, low-concentration species of high importance in atmospheric chemistry and new particle formation.