The earliest known train songs date to two years before the first public railway began operating in the United States . "The Carrollton March", copyrighted July 1, 1828, was composed by Arthur Clifton to commemorate the groundbreaking of the Baltimore & Ohio Railroad . Another song written for the occasion, "Rail Road March" by Charles Meineke, was copyrighted two days after Clifton's, one day before the July 4 ceremonies. The number of songs that have appeared since then is impossible to determine, not only because of the difficulties in documenting the songs but also in defining the genre. 
After downloading the Petcube app, you can link your phone up to the monolith, accessing the device’s camera. The Petcube senses motion in front of it, which lets you see what your animal’s up to but also takes weird videos of your feet if you step in front of it. Seeing your cat or doggo’s adoring face through the app is definitely heartwarming, but fair warning: watch your goddamn feet so weird photos don’t end up on some dark corner of the internet. Not that Petcube is going to sell pictures of your feet or anything (the images are in the app on your phone), but you can never be too careful these days. While the app saves your videos automatically, the quality isn’t great. Don’t expect Nat Geo-worthy screenshots.
Logistically, some sort of air traffic control system is going to need to be in place if the future is really going to include drone package delivery, medical drones , internet-delivery drones , and, of course, massive police surveillance . The skies are going to get too crowded and it’s too easy for bad actors to use drones for nefarious purposes . Even when people have no ill intent, the remote-controlled devices can cause chaos. Earlier this week , two planes fighting wildfires in Colorado had to prematurely drop their flame-retardant payloads because of drones flying in the area—a screwup that cost the US Forest Service somewhere between $16,000 and $20,000.