I use FlightAware <i>all the time</i>, but didn&#x27;t know they pull the data directly from the planes.<p>I&#x27;m guessing FlightAware is one half of the &quot;duopoly&quot; spoken about in the submission.<p>Edit:<p>Looks like the cost per 1k queries for flight arrival times is $7.90 USD, which is a Class 2 query @ $0.0079 USD per query at the highest tier [0], but it goes down with more queries.  You actually also probably want to pull their &quot;AirlineFlightSchedules&quot; API data to pull initial schedules for the day, which is a Class 1 query @ $0.0120 [0].<p>How many flights globally, per day?  ~100,000 [1].  Once you fall down into their tiered pricing, and use their &quot;15 results per query&quot; rule, it amounts to ~$80.  Once there is flight information for each flight for the day, there will likely be periodic update times.  There&#x27;s a firehose feed, but they don&#x27;t specify pricing, so I&#x27;m not sure what the cost is to provide live updates.<p>If we say 5 updates per flight (total guess), that becomes ~500,000 queries daily of Class 2 data.  I&#x27;m confident there&#x27;s a way to batch these, so this comes down to ~33,334 requests, which puts us at ~$181.34 in additional charges per day.<p>So our daily costs are now about ~$261.34, or ~$7,840.20 per month, assuming they&#x27;re not pulling data on-demand.  This changes somewhat significantly if an app (correctly IMO) only pulls data for flights it&#x27;s asked about.  You get to cut out the $80&#x2F;day entirely, and only some portion of the $181.34 is actually paid each day.  If you consider the ~28,500 domestic flights in the US [2], and if app users only search for half of those, costs drop to ~$162 per day, or $4,860 monthly (plus the unknown cost of the firehose).<p>So, because of the cost of the data alone, your app will have to pull in a bunch of users.  Wait, how many?  Let&#x27;s figure that out, based on an estimation strategy I pulled off of Quora (so it might be wrong) [3]:<p>Each user checks their flight status 3 times, which takes them ~1 minute overall to read, so we get 2 impressions [3].  I don&#x27;t really know what these other two things are, but I guess we&#x27;ll next assume 100% fill rate and eCPM of $3.  But that&#x27;s just per flight.  694 million passengers took flights in the US this year [4], and while I know we&#x27;re getting into some pretty speculative territory, that&#x27;s at <i>least</i> 2 flights per person per year, not to mention all the other people who also check on flight statuses of their friends&#x2F;family.  I feel comfortable saying that each person would check this app at least 15 times a year (you&#x27;d use it if you had it), or 0.04 times a day, which would give 0.08 impressions per day.<p>Our calculation is now:<p><pre><code>    (0.08n &#x2F; 1000) * $3 * 1.0 = $0.0002n

    $0.0002n = $162

    n = 810,000
</code></pre>
To cover costs for the data alone, you&#x27;d need 810,000 users.  Even if each person used this app twice as often, you&#x27;d still need 405,000 users.  That&#x27;s completely untenable.  I&#x27;m actually wondering if my math and assumptions are correct...<p><pre><code>    [0] http:&#x2F;&#x2F;flightaware.com&#x2F;commercial&#x2F;flightxml&#x2F;pricing_class.rvt
    [1] http:&#x2F;&#x2F;www.garfors.com&#x2F;2014&#x2F;06&#x2F;100000-flights-day.html
    [2] http:&#x2F;&#x2F;sos.noaa.gov&#x2F;Datasets&#x2F;dataset.php?id=44
    [3] https:&#x2F;&#x2F;www.quora.com&#x2F;How-much-ad-revenue-can-be-expected-per-100-000-downloaded-iPhone-iPad-apps
    [4] http:&#x2F;&#x2F;www.transtats.bts.gov&#x2F;</code></pre>