There are a few ways to make color pop. It starts by taking a good image. Assuming a middle to high end camera, shoot raw at the lowest ISO possible and get the exposure correct. Note that jpg files tend to look richer out of camera because the camera (or your iphone) does a lot of processing to get them that way based on your camera settings. To me, the first picture in your post is not very good with the bright sky taking too much of the frame and is way overexposed. Learning how to deal with high dynamic range situations like this take some skill and experience to overcome, so let's ignore HDR scenes in this reply. In post processing, you want as much contrast as possible, so after adjusting exposure and white point, make the deep shadows go to full black and the brightest highlight go to full white. Then apply a gentle S to the tone curve to make the colors pop. You can also play with the saturation and vibrance sliders to bring out certain colors.
Learning how to enhance images in Post Processing takes time and patience, which is why many shoot jpg, but even then, you need to learn your camera's settings and features to get the best jpgs possible.