The application has two trained models one with simple cully connected layers and one base on convolution.
At the beginning it will take some time(depending on network) until it downloaded the wights for the first time

Please be aware that although the performance on MNIST data set is quite high the images given by
the application when draw are quite different from what network was trained for.
Although the accuracy continues to be good, feel free to train with images from draw area and notice
how the networks become even better
You may want to increase the memory and also please be aware that it will take some time
to download the clean wights from VGG16 since at the beginning it downloaded the wights trained for dog and cat