Note 13 - Equity Incentive Plans (Tables)

9 Months Ended

Sep. 30, 2018

Notes Tables

Share-based Compensation, Stock Options, Activity [Table Text Block]

	Number of options			Weighted average exercise price (per share)		Weighted average remaining contractual term (in years)	Aggregate intrinsic value
Outstanding at December 31, 2016		1,225,000		$	0.17	2.62	$	83,425
Granted		4,650,000			0.26
Exercised		(300,000	)		0.13
Forfeited/cancelled/expired		(300,000	)		0.14
Outstanding at December 31, 2017		5,275,000			0.26	4.09	$	130,475
Granted		570,000			0.28
Exercised		(200,000	)		0.22
Forfeited/cancelled/expired		(2,975,000	)		0.25
Outstanding at September 30, 2018		2,670,000		$	0.27	3.58	$	396,500
Vested and exercisable at September 30, 2018		800,000		$	0.22	2.57	$	158,425

Share-based Compensation Arrangements by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding [Table Text Block]

Fair value of options vesting for the period ended	Number of options vested		Fair value of options vested
September 30, 2018		625,000	$	125,190
September 30, 2017		62,500	$	12,742

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

Awards breakdown by price range at September 30, 2018
			Outstanding						Vested
Strike price range ($)			Outstanding stock options		Weighted average remaining contractual life		Weighted average outstanding strike price		Vested stock options		Weighted average remaining vested contractual life		Weighted average vested strike price
0.00	to	0.20		250,000		0.74	$	0.17		250,000		0.74	$	0.17
0.21	to	0.30		1,695,000		3.79		0.26		550,000		3.40		0.25
0.31	to	0.50		725,000		4.07		0.34		-0-		0.00		0.00
0.00	to	0.50		2,670,000		3.58	$	0.27		800,000		2.57	$	0.22

Awards breakdown by price range at December 31, 2017
			Outstanding						Vested
Strike price range ($)			Outstanding stock options		Weighted average remaining contractual life		Weighted average outstanding strike price		Vested stock options		Weighted average remaining vested contractual life		Weighted average vested strike price
0.00	to	0.20		300,000		1.93	$	0.18		250,000		1.48	$	0.17
0.21	to	0.30		4,250,000		4.12		0.25		150,000		1.30		0.22
0.31	to	0.50		725,000		4.82		0.34		-0-		0.00		0.00
0.00	to	0.50		5,275,000		4.09	$	0.26		400,000		1.42	$	0.19

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

	Stock option assumptions for the period ended
Stock option assumptions	September 30, 2018	December 31, 2017
Risk-free interest rate	2.71%	1.81%
Expected dividend yield	0.0%	0.0%
Expected volatility	110.3%	127.1%
Expected life of options (in years)	5	5

Share-based Compensation, Activity [Table Text Block]

	Weighted average grant date fair value
	for the period ended September 30,
	2018		2017
Stock options granted during the period	$	0.23	$	0.19
Stock options vested during the period	$	0.20	$	0.20
Stock options forfeited during the period	$	0.19	$	0.13

Schedule of Nonvested Share Activity [Table Text Block]

	Shares underlying stock options		Weighted average grant date fair value
Nonvested shares at January 1, 2018		4,875,000	$	0.21
Nonvested shares at September 30, 2018		1,870,000	$	0.24