Are my photos too big?

Alright, so this is sort of my last resort. I use a Nikon d3200 camera and I want to put a filter from the iPhone app VSCO Cam on a photo I took yesterday. Everything goes fine until I try saving the filtered photo onto my camera roll- when I choose save as "FULL / MAXIMUM FILE SIZE", the app starts to save it but then shuts down! I can save the photo as "LARGE / 1024px", but it looks blurry when I do that! Can anyone help me please?

Downsize the photo in an editing program (Microsoft Paint will do) on your computer, then put it back onto your iPhone and apply the filter.

For example, you cut put the smaller version of the photo on an image sharing site like Tinypic or Photobucket, then you could go back onto your iPhone and save it.

I'm not sure why you would take a good photo, then attack it with an "app" and put it onto a telephone, but hey…

Always always always take photos at the biggest size and best quality settings.
Then make a copy, rename it, and play with IT.

It is very easy to resize (i.e. Make smaller) a photo - pretty much every single piece of software or photo related website lets you do that - your choices for this are vast.

Now you have a clear, resized photo plus a full sized, untouched original for future reference.