Note 5 - Shareholders' Equity (Tables)

6 Months Ended

Jun. 30, 2021

Notes Tables

Share-based Payment Arrangement, Option, Activity [Table Text Block]

	Outstanding Options
	Number of Shares			Weighted Average Exercise Price
Balance at January 1, 2021		3,589,783		$	0.36
Options granted		998,450			0.36
Options exercised		(154,271	)		0.43
Options forfeited/expired		(90,729	)		0.78
Balance at June 30, 2021		4,343,233		$	0.35
Exercisable, June 30, 2021		2,707,124		$	0.38
Vested and expected to vest		3,861,412		$	0.35

Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	Three months ended June 30,				Six months ended June 30,
	2021		2020		2021		2020
Type of awards:
Stock options	$	28	$	27	$	81	$	63
Restricted stock		-		5		-		10
	$	28	$	32	$	81	$	73
Income statement account:
Selling and marketing	$	6		7	$	25	$	16
General and administrative		22		25		56		57
	$	28	$	32	$	81	$	73

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Six months ended June 30,
	2021			2020
Expected dividend yield		—			—
Expected stock price volatility		74.8	%		73.4	%
Risk-free interest rate		0.7	%		1.4	%
Expected term (in years)		5.8			5.6
Weighted-average grant date fair-value	$	0.23		$	0.18