Doodle-based graphical passwords represent a challenging scenario due to their high variability and the tendency to be graphically simple. Despite this, doodle-based authentication using touch screens is a promising lightweight user verification method. Several works have been published in this field, although they report in general experimental verification results over small and private databases. In this paper we analyze the performance of several state-of-the-art systems for doodle verification, using the recently acquired DooDB database, which is publicly available. Several algorithms are tested, from the fields of gesture recognition and doodle and signature verification. A comparative study of their performance is done, and future research directions are pointed out.