In the Invoice Ninja version of the application (I can’t find the version number in the latter – it used to be in the About icon in the lower-left-hand corner), the Task report CSV output is not aggregating properly.
The Duration column appears to include the number of seconds summed for all of the entries for a task, while the report appears to return a separate line for each entry in a task (probably because it is pulling the Start Date and End Date for each entry). Either the report needs to be fixed so that each row represents all of the entries for a task aggregated (with a min Start Date and max End Date for all entries), or each row represents one entry (of possibly many) for a task (with the correct, unsummed Duration for each entry).
Separately, I am kind of frustrated by the removal of features from the app. I used to have at least 2 ways of quickly getting aggregated information on Tasks: first on the Dashboard, where it would show me Task amounts per day, and second in the Reports, where the app would show me aggregated information without having to download a CSV and pivot it (which, because of the aggregation issue reported above, requires additional preprocessing). I hope that you would consider restoring some of the functionality from the old app to the new app.