For a better experience in Iconglossary it is recommended to access it from a device with an 11 inch screen minimum so that the click sensitive areas of small size work effectively. If you access it from a device with a smaller screen the activities work but it is harder to enjoy since you will have to enlarge the images each time so that these small click sensitive areas function.
Also, your device should support a rather adequate internet speed for the parts of the activities which call animated images. If you do not have such a device you have to run these activities for the first time and then wait until the animated images are uploaded. This first time the animated pictures will not behave properly but the second time you will run Iconglossary, all will work fine!
Useful practical advice
The clicks on the word and then on its image (or vice versa) should be successive and paired (word-image or image-word), without any other click in between, so that the result is right.
Also, since the activities require multiple clicks, if somebody overdoes it while exploring and clicking around, there is a chance that the functionality of the activity is blocked at that point. By refreshing the browser all will come back to normal.