One of the features of Baby ESP that isn't immediately obvious is that you can customize which buttons show up on the main screen of the app and in the widget.

To do so long-press the button you want to replace on the main screen of the app (press and hold the button for a second or two).  You will then get a popup window to select a new button.

If you have custom other activities or medicines you can add a picture for those activities to show up as the icon.  To add/edit the images used for other activities go to the Other screen or Medicine screen, then long-press the activity.  A popup window will appear, tap the image icon in the upper left and you can then take a picture or select an existing image from your Gallery.