| Segment reporting | 
 The following
tables summarize segment information for the three and nine months ended June 30, 2015 and 2014:   
    |  |  | Three
    Months Ended June 30, |  |  | Nine
    Months Ended June 30, |  |  
    |  |  | 2015 |  |  | 2014 |  |  | 2015 |  |  | 2014 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | 2,565,330 |  |  | $ | 2,197,324 |  |  | $ | 14,042,094 |  |  | $ | 2,361,716 |  |  
    | Services |  |  | 374,075 |  |  |  | 477,082 |  |  |  | 1,168,342 |  |  |  | 1,584,181 |  |  
    |  |  | $ | 2,939,405 |  |  | $ | 2,674,406 |  |  | $ | 15,210,436 |  |  | $ | 3,945,897 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Gross profit (loss) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | 809,253 |  |  | $ | (111,149 | ) |  | $ | 5,268,391 |  |  | $ | (99,750 | ) |  
    | Services |  |  | 333,793 |  |  |  | 406,097 |  |  |  | 1,046,707 |  |  |  | 1,299,182 |  |  
    |  |  | $ | 1,143,046 |  |  | $ | 294,948 |  |  | $ | 6,315,098 |  |  | $ | 1,199,432 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Operating income (loss) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | (4,414,858 | ) |  | $ | (1,801,774 | ) |  | $ | (6,954,605 | ) |  | $ | (3,679,769 | ) |  
    | Services |  |  | 271,221 |  |  |  | 330,239 |  |  |  | 853,739 |  |  |  | 811,643 |  |  
    |  |  | $ | (4,143,637 | ) |  | $ | (1,471,535 | ) |  | $ | (6,100,866 | ) |  | $ | (2,868,126 | ) |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Depreciation and amortization |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | 165,205 |  |  | $ | 123,119 |  |  | $ | 490,659 |  |  | $ | 325,134 |  |  
    | Services |  |  | 3,347 |  |  |  | 4,396 |  |  |  | 10,040 |  |  |  | 13,618 |  |  
    |  |  | $ | 168,552 |  |  | $ | 127,515 |  |  | $ | 500,699 |  |  | $ | 338,752 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Interest Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | 5,678 |  |  | $ | 172,708 |  |  | $ | 4,202,622 |  |  | $ | 284,082 |  |  
    | Services |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    |  |  | $ | 5,678 |  |  | $ | 172,708 |  |  | $ | 4,202,622 |  |  | $ | 284,082 |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Net income (loss) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | (4,479,612 | ) |  | $ | (1,994,740 | ) |  | $ | (11,104,784 | ) |  | $ | (3,862,580 | ) |  
    | Services |  |  | 271,221 |  |  |  | 452,839 |  |  |  | 853,739 |  |  |  | 936,667 |  |  
    |  |  | $ | (4,208,391 | ) |  | $ | (1,541,901 | ) |  | $ | (10,251,045 | ) |  | $ | (2,925,913 | ) |    
    |  |  | As of |  |  | As of |  |  
    |  |  | June 30, |  |  | September 30, |  |  
    |  |  | 2015 |  |  | 2014 |  |  
    | Total Assets |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | 15,297,836 |  |  | $ | 18,118,425 |  |  
    | Services |  |  | 163,361 |  |  |  | 171,021 |  |  
    |  |  | $ | 15,461,197 |  |  | $ | 18,289,446 |  |  
    |  |  |  |  |  |  |  |  |  |  
    | Intangible assets |  |  |  |  |  |  |  |  |  
    | Marketplace platform |  | $ | 4,892,586 |  |  | $ | 4,234,692 |  |  
    | Services |  |  | 4,605 |  |  |  | 6,422 |  |  
    |  |  | $ | 4,897,191 |  |  | $ | 4,241,114 |  |    |