The last few days I saw a new filter on many pages on instagram that changes the sky and it looks like in the following pictures.
Can you tell me what is it?
Looks like "sunset" to me. You can only use it once every 24 hours though - so only the pros and the lucky tend to wait around for it.
Google "Arizona sunset". Some places on this earth just get amazing colors. No filter required. Though, it is possibly the natural colors were simply over saturated in post in your examples.
The image of the woman reclining appears to be a composite. The woman and the sky were not taken at the same time. You can see this as the direction of the light, it's color and contrast are completely different.
The look of the other images can easily be recreated simply by increasing the saturation or vibrance. Try using Adobe Lightroom mobile which makes all of these edits very simple to do with your phone.
Just do yourself a huge favor and always keep an un-edited backup copy. Your tastes will change many times over time. The last thing you want is to have a bunch of important images that were all edited in a way that you will hate sometime in the future. Especially when you consider that the way that these photos were edited is really downright awful and should be avoided. We all do this. We all have images that have been overcooked (i.e. over processed). We get a new app and then go hog wild with the editing because, well, we can. But that often leads to really bad work. It's just at the time, the look is different and we perceive that different look to be cool because of its uniqueness when in reality, it's really bad.