In germany we distinguish between this and last month. So if I wanna search in june, I use this month, if I want to search in may I use last month. And neither of both is like last 30 days form me.

I would be confused

"Will users misunderstand x" the answer is always yes, the real question is how many do and if you care about them.

If this was June (any date) I would expect "Last month" to be a search in (all of) May (and excluding June completely).

Last month = last 30 days for me. And based on this very small sample of responses I'd say that 'last month' is ambigious and you'd be better off using 30 days not 'last month'. If you need a bigger sample of responses ask around your office / your friends what people understand by 'last month'.

If something says it will show 'last month', people will expect the range to be the last calendar month not the last 30 days.

I would ditch the "last", so it would become All|365 days|30 days...

Yes, this is definitely confusing. "Last month" means "The last complete calendar month", not "The preceding 30 days". On July 31st, for example, the user would expect June's data, while your application would provide July's data.

@NickGammon but that would be a silly feature, so you might consider that it means something else, no?

on a side note, I don't see the point of the feature. The result is going to be a list anyway, and each subsequent category simply removes elements from the list. But if the user is scrolling anyway, they'll have to scroll past the last week, last month, and last year before arriving the year before that no matter what. I don't think this filter is going to help the user experience much

I would think of past week to mean last 7 days. But last week as a calendar week. Past month should mean previous 30 days (except that months are not always 30 days for some reason), but some might disagree. It is like the question: when does "this weekend" become "last weekend" and when does "next weekend" become "this weekend"? Usually some time during Monday when you are talking to people about "what you did this weekend". But no one would be confused about "past 2 days". So there you go, language is not always as helpful or precise as we would wish.

That's how Reddit does it. After almost 4 years I'm still not sure what they mean. I find it confusing.

Some iOS specific feedback: consider not using a UISegmentedControl for this. If you ever want to internationalize your app, it's going to be very difficult with this design; if English "barely fits", there will almost certainly be other languages where this is still an issue. Consider a picker instead. Alternatively, set adjustsFontSizeToFitWidth to YES with a minimumScaleFactor on all of your labels which will allow text to shrink to fit the available space (but don't make it too small!).

but that would be a silly feature, so you might consider that it means something else - I would not be certain what it meant. For example "yesterday" would not mean "in the last 24 hours" to me.

Oh yes. I worked on an early contact management system in the late 80's. Managers would mean something different by "next thursday" than techies, etc.

As a user I understand that if I flip a coin to predict if "last week" means last 7 days or the last calendar week in an arbitrary piece of software I'll have a 50% chance of getting it correct regardless of if I use heads = 7 days, tails = calendar week, or flat sides = 7 days, curved edge = calendar week.

"Last week" does not mean "last seven days"

Another thing to consider is next. If it's Monday, and I say "Next Thursday", I don't mean 3 days from now, I mean 10 days from now. It all boils down to context. If, on that same Monday, I say this Sunday I will do x, I'm talking about 6 days from now. If I said this Sunday I went to the lake, I'm talking about the day before. If I say next Sunday I will go to the movies, I'm talking about 13 days from now.

@Physics-Compute if that were the case, and last and next were objective, this question wouldn't have come up in the first place.