Exhibit 31.1

**CERTIFICATION**

I, John J. Sims, certify that:

| 1.     | I have reviewed this quarterly report on   Form 10-Q of 724 Solutions Inc.;                                                                                                                                                                                                                                         |
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| 2.     | Based on my knowledge, this report does not   contain any untrue statement of a material fact or omit to state a material   fact necessary to make the statements made, in light of the circumstances   under which such statements were made, not misleading with respect to the   period covered by this report;  |
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| 3.     | Based on my knowledge, the financial   statements, and other financial information included in this report, fairly   present in all material respects the financial condition, results of   operations and cash flows of the registrant as of, and for, the periods   presented in this report;                     |
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| 4.     | The registrant’s other certifying officers   and I are responsible for establishing and maintaining disclosure controls   and procedures (as defined in Exchange Act Rules 13(a)-15(e) and 15(d)-15(e))   and for the registrant and have:                                                                     |
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|   | a)                                                                                                                                                                                                                                                                                                                  | Designed such disclosure controls and   procedures, or caused such disclosure controls and procedures to be designed   under our supervision, to ensure that material information relating to the   registrant, including its consolidated subsidiaries, is made known to us by   others within those entities, particularly during the period in which this   report is being prepared; |
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|   | b)                                                                                                                                                                                                                                                                                                                  | Evaluated the effectiveness of the   registrant’s disclosure controls and procedures and presented in this report   our conclusions about the effectiveness of the disclosure controls and procedures,   as of the end of the period covered by this report based on such evaluation;   and |
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|   | c)                                                                                                                                                                                                                                                                                                                  | Disclosed in this report any change in the   registrant’s internal control over financial reporting that occurred during   the registrant’s most recent fiscal quarter that has materially affected, or   is reasonably likely to materially affect, the registrant’s internal control   over financial reporting; and |
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| 5.     | The registrant’s other certifying officers   and I have disclosed, based on our most recent evaluation of internal control   over financial reporting, to the registrant’s auditors and the audit   committee of registrant’s board of directors (or persons performing the   equivalent functions): |
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|   | a)                                                                                                                                                                                                                                                                                                                  | All significant deficiencies in the design   or operation of internal control over financial reporting are reasonably   likely to adversely affect the registrant’s ability to record, process,   summarize and report financial data; and |
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|   | b)                                                                                                                                                                                                                                                                                                                  | Any fraud, whether or not material, that   involves management or other employees who have a significant role in the   registrant’s internal control over financial reporting. |