Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

5. STOCK OPTIONS AND WARRANTS (Details Narrative)

v3.19.1

5. STOCK OPTIONS AND WARRANTS (Details Narrative) - USD ($)	3 Months Ended		9 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2019	Jan. 31, 2018	Apr. 30, 2018
Stock based compensation - options			$ 282,673	$ 766,382
Options [Member]
Options outstanding	96,450,000		96,450,000		95,250,000
Options granted in period			1,200,000
Aggregate intrinsic value	$ 0		$ 0
Aggregate intrinsic value per share			$ 0.042
Non-Employee Options [Member]
Options granted in period			1,200,000	5,400,000
Stock based compensation - options	21,000	$ 57,000	$ 78,000	$ 154,000
Unrecognized compensation expense	24,000		$ 24,000
Unrecognized compensation expense weighted-average period			5 months
Employee Options [Member]
Options granted in period			0	10,750,000
Stock based compensation - options	51,000	$ 220,000	$ 205,000	$ 612,000
Unrecognized compensation expense	$ 0		$ 0
Warrants [Member] \| Placement Agent [Member] \| May 24, 2017 [Member]
Warrants issued, shares				833,333
Aggregate fair value of warrants issued				$ 20,000
Warrants [Member] \| Placement Agent [Member] \| July 26, 2017 [Member]
Warrants issued, shares				2,000,000
Aggregate fair value of warrants issued				$ 39,000
Warrants [Member] \| Placement Agent [Member] \| May 30, 2018 [Member]
Warrants issued, shares			1,388,889
Aggregate fair value of warrants issued			$ 19,000
Warrants [Member] \| Placement Agent [Member] \| June 28, 2018 [Member]
Warrants issued, shares			1,923,077
Aggregate fair value of warrants issued			$ 38,000
Warrants [Member] \| Placement Agent [Member] \| November 1, 2018 [Member]
Warrants issued, shares			2,272,727
Aggregate fair value of warrants issued			$ 19,000

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