We have spent more than 1 week at this apartment and we liked it. The hosts (Sylvie) speaks English and with her husband are always there to help and advice. The place is very clean and well equipped. There are 2 bathrooms ( tiny and normal one), one hall with a very functional kitchen, sofa and 1 bedroom. The location is not a central one , if this is important to you. We experienced Internet/wifi problem during our stay, most of the time the signal was very weak and available only from one place at the balcony. Hosts tried their best to fix the problem, but it still didn't work. Other than that everything was very nice and pleasant.
Also hosts have a restaurant downstairs called New Africa. This could be one of your best choice to eat , amazing cuisine, but prices are European, not African, yet it worth trying, really good and clean place and always full of people. They organize dancing classes there on Saturdays, so be aware of a loud music till 2am. I used earplugs, so it didn't disturb me.
Breakfast is optional for additional cost, but we never tried it, as there is boulangerie nearby and a coffee /tea option inside the apparent.
We also liked European style and approach to delivering service in this place, which appeared to be safe and nice for me and my husband. Thank you, Sylvie!
Enjoy your trip to Senegal!