Stock-based compensation (Details 1) - 2013 Equity Incentive Plan - USD ($)	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Options
Exercised	(622,000)	(628,000)
Stock options
Options
Outstanding	3,141,876	4,120,074
Granted	750,000	332,500
Exercised	(449,500)	(719,448)
Forfeited	(610,750)	(591,250)
Outstanding	2,831,626	3,141,876	4,120,074
Vested options	2,732,876
Remaining options expected to vest	544,000
Weighted Average Exercise Price per Share
Outstanding	$ 0.21	$ 0.25
Granted	0.40	1.48
Exercised	0.44	0.22
Forfeited	0.88	0.38
Outstanding	$ 0.34	$ 0.21	$ 0.25
Weighted Average Remaining Contractual Term (Years)
Weighted Average Remaining Contractual Term (years), Outstanding	4 years 4 months 17 days	5 years 2 months 23 days	5 years 8 months 1 day
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$ 804,744	$ 6,168,665	$ 2,397,883

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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- Definition

Weighted average price of options that were either forfeited or expired.