You could go to one of these websites:http://www.esl-lab.com/https://www.eslpod.com/website/index_new.html
(only if you are able to use the computer or even the phone in these 60 minutes left)
You could listen to podcasts or even try to watch a video, a movie or even an episode of a tv show in English, if you have any problems don't understanding what is beind said try to watch it with subtitles in English, that will help you to catch and don't miss the point of the conversation. I highly recommend you this one website (http://ororo.tv/en
) it has a huge variety of programs, only the movies I think you need to have an account to watch it, but it may be worth if you really enjoy watching movies/series.
If you think that reading is a better option (even thinking that you would have already done a lot of grammar study in these 120 minutes on duolingo and Englishtown) you could simply go to websites like BBC or CNN you can find pages about culinary, science, culture, politics... I'm currently using duolingo, but I just found Lingq.com, a website for language learners (in your case English) made by a polyglot, it has a lot of recommendations and people say that it is very effective and the studies can be done effortlessly, some of its users have already said that in only 6 months they've gotten pretty close from their wanted fluency (very similar to the native speakers).
Lastly you should look online to find websites or even PDFs of English grammars. It's not necessary to buy any grammar, as you said if you get it at the nearest labrary, when using it try to get the content you learnt and then make sentences or even write a situtation, or even write about your day so you will be practicing and what you did during the day will finally be very effective. Sorry if I did a lot of deviations on the point while writing this answer. Hope it can be useful and help you ion your daily studies, don't forget, try to have fun when learning a new language, it becomes much more easy to learn.