An iPhone* app available through the Apple App Store allows you to take photos of the sky and contact your government representatives (USA only presumably). The concern of the app creators is that there is a widespread spraying program in place (again, in the USA only?) with the goal of "Climate Change and it's [sic] side effects include extreme weather, ozone depletion, drought, storms, air pollution, water pollution, and the intentional blocking of the sun."
The app allows users to snap photos of alleged dangerous spraying and weather mofication by aircraft and then "directly contacts legislators and petitions for these activities to cease and desist."
Here's their description of what the app can be used for:
"You have the right to breathe clean air, drink clean water, and to enjoy natural sunshine. SkyderALERT enables you to easily capture visual evidence by photographing planes spraying the sky, or the aftermath of persistent contrails blocking the sun."
A beautiful solar halo, hazy cirrus, and some contrails, seen at UVic on 2014-03-25. No "spraying" required.
As far as I can tell there's no legal barrier to selling an app for the purpose of helping users contact government officials. That's perfectly fine, though in this case it's a waste of time for both sides of the communication. The issue is the claim of the app creator that there is a program that "uses planes to release toxic chemicals into the atmosphere", and "planes spraying the sky" leaving an "aftermath of persistent contrails [that] block the sun." Claims like these are not supported by evidence. There is no spraying program, no secret conspiracy, there are simply no "chemtrails". These are conspiracy theories and have no basis in reality. A great site that thoroughly debunks many of the ideas of the "chemtrail" believers is Contrail Science.
The creators of the app do make a pretence of aligning themselves with science in much of the language on their website. The problem here is that the many scientific, peer reviewed papers that they have linked to, do not actually support their claim that there is an ongoing program of "planes spraying the sky". What these papers do indicate is that there is an active research effort the goal of which is to better understand the possibilities of wide-scale geoengineering, what kind of technology exists or would need to be developed, what we know about clouds and cloud properties, and so on. It's a catalogue of possibilities and options. Some believe that this kind of research is going to be vital in our attempts over the next 100 or more years to keep anthropogenic climate change in check. However, these papers do not demonstrate that there is a program in operation at the moment. It's ludicrous to imagine such a program in any case as the scale would be astonishing and couldn't be kept secret. Of course there is a massive international effort to do research on geoengineering. One of the biggest projects is "GEOMIP". You can read more about that effort at their website.
This app may be useful for helping USA citizens find and contact their government representatives but otherwise it's a waste of your time.
*There's an Android version as well