Stockholders Deficit (Tables)

12 Months Ended

Dec. 31, 2017

Summary of Stock-Based Compensation

The Company incurs stock-based compensation expense relating to the grants under its equity incentive plans of RSUs and stock options to employees, non-employee directors and consultants of the Company and its affiliates and through its employee stock purchase plan. Amounts recognized in the accompanying statements of operations with respect to the Company’s stock-based compensation and employee stock purchase plan were as follows:

	Years Ended December 31,
	2017		2016
Selling, general and administrative	$	1,012,253	$	721,473
Research and development		319,916		217,553
Cost of revenue		103,918		63,102
	$	1,436,087	$	1,002,128

Summary of Stock Option Plans Activity

The following table summarizes stock option activity during the two-year period ended December 31, 2017:

	Number of Shares			Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value
Balance at January 1, 2016		736,645		$	4.18	7.5		$	947,794
Granted		563,400			2.46
Exercised		(11,093	)	2.15				$	2,126
Forfeited		(70,754	)	4.6
Expired/Cancelled		(56,493	)	3.97
Balance at December 31, 2016		1,161,705		$	3.35		7.7	$	36,887
Granted		494,500			2.09
Exercised		(41,815	)	2.68				$	152,130
Forfeited		(81,676	)		2.64
Expired/Cancelled		(14,943	)		6.15
Balance at December 31, 2017		1,517,771		$	2.97		7.5	$	67,242
Vested and expected to vest at December 31, 2017		1,517,771		$	2.97		7.5	$	67,242
Exercisable at December 31, 2016		593,670		$	3.46		6.4	$	28,822
Exercisable at December 31, 2017		851,996		$	3.31		6.5	$	248

Summary of Material Factors Incorporated in Black-Scholes Model In Estimating Fair Value of Options Granted

The material factors incorporated in the Black-Scholes model in estimating the fair value of the stock options granted for the periods presented were as follows:

	2017	2016
Fair value of common stock	$1.71 - 3.46	$1.98 - 2.88
Risk-free interest rate	1.75% - 2.20%	1.13% - 2.08%
Expected volatility	58.5% - 62.6%	59.9% - 93.7%
Expected term	5.1 to 6.3 years	4.8 to 6.2 years
Expected dividend yield	0%	0%

Summary of RSU Award Activity

The following table summarizes RSU award activity during the two-year period ended December 31, 2017:

	Number of Shares			Weighted- Average Grant Date Fair Value Per Share
Balance at January 1, 2016		27,500		$	5.45
Granted		389,761			2.43
Vested		(36,762	)		2.90
Forfeited		(25,000	)		2.46
Balance at December31, 2016		355,499		$	2.41
Granted		10,000			1.75
Vested		(336,333	)		2.47
Forfeited		(2,500	)		2.46
Balance at December 31, 2017		26,666		$	2.78
Vested and expected to vest at December 31, 2017		26,666		$	2.78

Employee Stock Purchase Plan

Summary of Material Factors Incorporated in Black-Scholes Model In Estimating Fair Value of Options Granted

The material factors incorporated in the Black-Scholes model in estimating the fair value of the ESPP awards for the periods presented were as follows:

	2017	2016
Fair value of common stock	$2.11 - 3.17	$3.03 - 4.09
Risk-free interest rate	0.61% - 1.12%	0.41% - 0.48%
Expected volatility	68.0% - 70.0%	70.0%
Expected term	0.5 years	0.5 years
Expected dividend yield	-%	-%