ictime works with detailed permissions that can be asigned based on JIRA groups (see ictime Permissions). So you can flexibly create the user roles you need; e.g. a user does not need to be an aministrator in JIRA to have access to administrative functionality in ictime.
As a special feature, we offer a workaround to cover missing JIRA permissions regarding viewing time tracking data in JIRA (see JIRA View Time Tracking Permissions).
Please keep in mind that additional JIRA permisions are required to use time tracking or might be useful to correctly configure users ("work on issues" permission is required; edit & delete work log permissions might be useful; http://confluence.atlassian.com/display/JIRA/Managing+Project+Permissions) and time tracking needs to be activated (see http://confluence.atlassian.com/display/JIRA/Configuring+Time+Tracking). See also JIRA Configuration and Permissions.