Major medical device makers haven't exactly rushed to integrate smartphones and tablets into their product lineups, despite their ubiquity and obvious potential medical utility. But now St. Jude Medical ($STJ) has gained a CE mark and launched the first app-based, wireless system for use during an initial patient trial period with an external neuromodulation chronic pain treatment device prior to receiving a permanent implant.The app is part of a larger push for St. Jude to gain ground in neuromodulation, which is key to its strategy to ramp up revenue growth this year and next.Dubbed the Invisible Trial System, it uses an external pulse generator (EPG) that can be controlled by the patient via an iPod app. The small EPG system is worn under a patient's clothes. An iPad mini tablet is used by the physician to set the programming parameters and to display trial usage data from the EPG. The EPG, patient iPod and physician iPad mini are all designed to communicate wirelessly via Bluetooth, thereby entirely eliminating the necessity for connecting cables."I expect that the St. Jude Medical Invisible Trial System will significantly improve the trial experience for my patients," said Dr. Stefan Schu, a neurosurgery specialist and senior neuromodulation physician at the Sana Clinic in Duisburg, Germany, in a statement.He continued, "The new system will be discreet, familiar and require no cables that can be uncomfortable or potentially cause the lead to dislodge. Perhaps the most important feature is the therapy itself, which will enable a unique Burst stimulation mode that will expand the range of stimulation modes available in the trial phase and thereby potentially improve the trial success rate for my patients suffering from chronic pain."The new trial system offers both traditional and burst stimulation modes. The latter has been shown to minimize paresthesia, an unpleasant tingling sensation that can accompany neuromodulation. That's also one of the prominent features of the recently approved chronic pain system Senza from emerging competitor Nevro ($NVRO)."We've developed our new patient-centric Invisible Trial System as a response to physician and patient feedback," said Dr. Eric Fain, group president at St. Jude, in a statement. The system "was designed to improve the comfort and usability of our system for patients evaluating spinal cord stimulation therapy to alleviate their chronic pain without focusing on potential barriers such as programming trial cables and systems with complex trial controls."