Balance Sheets - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 10,796,072	$ 3,686,302
Accounts receivable, net of allowance of $398,847 and $361,350 in 2018 and 2017, respectively	5,021,111	4,287,255
Inventories, net	1,191,666	1,146,971
Prepaid expenses and other current assets	963,700	750,085
Total current assets	17,972,549	9,870,613
Property and equipment, net	343,693	592,688
Intangible assets, net		159,470
Other assets	198,365	44,432
Total assets	18,514,607	10,667,203
Current liabilities:
Accounts payable	1,726,360	1,654,101
Accrued liabilities	2,642,481	3,195,247
Deferred revenue	5,825,536	5,702,769
Warrants		19,574,977
Total current liabilities	10,194,377	30,127,094
Long-term deferred revenue	407,151	611,863
Other liabilities	641,461	535,369
Total liabilities	11,242,989	31,274,326
Convertible Preferred stock:
Convertible Preferred stock, par value $0.001; 10,000,000 shares authorized, 23,900 shares outstanding at 2018 and 2017	5,960,475	5,960,475
Stockholders' equity (deficit):
Common stock, par value $0.001; 300,000,000 shares authorized, 59,058,297 and 22,805,731 shares issued at 2018 and 2017, respectively	59,058	22,806
Additional paid in capital	478,179,574	450,748,403
Treasury stock, 4,015 shares at 2018 and 2017	(205,999)	(205,999)
Accumulated deficit	(476,721,490)	(477,132,808)
Total stockholders' equity (deficit)	1,311,143	(26,567,598)
Total liabilities and stockholders' equity (deficit)	$ 18,514,607	$ 10,667,203