CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016
CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS
Revenues, net	$ 100	$ 64
Cost of goods sold	516	237
Gross deficit	(416)	(173)
Operating expenses:
Research and development	10,158	5,702
Sales and marketing	3,198	5,109
General and administrative	4,654	4,174
Total operating expenses	18,010	14,985
Loss from operations	(18,426)	(15,158)
Change in fair value of warrant liability	163
Other expense, net	(141)	(436)
Loss before income taxes	(18,404)	(15,594)
Provision for income taxes	2	4
Net loss and comprehensive loss	(18,406)	(15,598)
Accretion on Series A convertible redeemable preferred stock		(202)
Deemed dividend on Series A convertible redeemable preferred stock		(201)
Deemed dividend on Series A convertible preferred stock	(126)
Net loss available to common stockholders	$ (18,532)	$ (16,001)
Basic and diluted net loss available to common stockholders per share	$ (0.52)	$ (0.89)
Shares used in computing basic and diluted net loss per share	35,806,000	17,950,000