I usually take pictures on my phone as it's always with me, but for this specific situation, the telephoto lenses restrict too much light, and so the image becomes too noisy and artifactey as the phone tries to compensate for it being under-exposed.
As for the upload limits, i was able to upload the photo at a much larger size (~8mb), but it failed to show a preview of the image, so i had to scale it down even more.