the driver and twowo passengs, killed. philelphia police, blaming speed. surveillance video showing the girls speeding by moments before the crash. abc affiliate wpvi now reporting investigators are looking into whether the popular app snapchat also played a role. her uncle believes it did. >> one friend said she was snapchatting all night. in the car they were showing their speed, how fast they were driving. what they were doing. >> reporter: he says his niece was using a special filter on snapchat which snaps, or records, their speed. a popular trend he believes encourages people to drive fast and share with friends online. >> the fact that that part of the app is on there seems irresponsible. >> if that happened, it helped to kill my daughter. >> reporter: a snapchat spokesperson telling abc news they take distracted driving seriously, including a do not snap and drive warning message when this geofilter is first acaccessed. gia's family, now warning others. >> i'm not blaming this, but i hope someone gets something from this and puts it down while they

it could seat the traditionaltr three passengers, shift to twowo people who need additional space, including overweight passengers, or even fit a fourthen person, like two parents and two small children. >> the airlines will consider anything that allows them to make a buck. >> reporter: ben mutzabaugh is the editor of "usa today's" "today in the sky" blog. >> if we've seen nothing else in the airline industry, they're very clever about coming up with ways to sell seats to passengers, especially when they can charge more for either seats that are better or for seats that are less awful. >> reporter: airbus previously sought patents for a design stacking passengers and thismi semi-standing concept. seat maker zodiac created a hexagon pattern where the middlees aisle and window while adding up to 30 more passengers per plane.ma tennessee congressman stephen cohen worries extra seats could jeopardize safety making it harddi to evacuate within the required 90 seconds as seen in this video. he's authored a bill requiring the f.a.a. to set minimum seat- size standards. >> if people can't get out o