Its alright...

But it needs updating or fixing. I accidentally entered the wrong end date of my period and now I cant delete it. Deletion needs to be added, or it needs to be simpler to do as I cant figure out how to do it. It now says my period was 41 days long. Wow...
I dont get what the graphs are for. Just for fun?
I like that it predicts your next cycle. For me, its 75% right for when my period is supposed to start, plus or minus one week. My cycles can be unpredictable at times though...

maishengher about Simple Period (Period Calendar), v3.3