Which one is best?
Which one do you personally like better?? [name_f]Hallie[/name_f] sounds softer and more delicate than [name_f]Callie[/name_f]. [name_m]Both[/name_m] are really cute. If you want the name to be less common, I believe [name_f]Hallie[/name_f] is the way to go. [name_f]Callie[/name_f] isn’t super popular but I think it is more common.
Personally, I am leaning towards [name_f]Hallie[/name_f]. I think both are very cute.
I think I would prefer to see each with a full given name, so [name_f]Hallie[/name_f] or [name_f]Callie[/name_f] would be nicknames. They both seem very nickname-y to me. I do realize each are full first names and certainly have the strength to be full given names.
[name_f]Callie[/name_f] could be short for [name_f]Callista[/name_f], [name_f]Camille[/name_f], [name_f]Camilla[/name_f], Caliope, or even [name_f]Carolyn[/name_f]
[name_f]Hallie[/name_f] could be short for [name_f]Helena[/name_f], [name_f]Thalia[/name_f], [name_u]Hillary[/name_u], etc. I also realize my nickname ideas seem to stretch limits, but I love nicknames, and nicknames seem to have a casual and fun versatility which is so inspiring to me. 
I prefer [name_f]Callie[/name_f] as a full name, [name_f]Hallie[/name_f] as a nickname for [name_f]Helena[/name_f].
Neither is my style. They’re just too cutesy for a full name. If I had to choose, I would go with [name_f]Callie[/name_f]. There aren’t many Callies around compared to the prevalence of [name_f]Hallie[/name_f] names and their multiple spellings.
I think [name_f]Callie[/name_f] is cute. It strikes me as happy and kind of floral.
I prefer [name_f]Callie[/name_f], because [name_f]Hallie[/name_f] doesn’t have any substance as a full name.
I prefer [name_f]Hallie[/name_f]
I personally prefer [name_f]Callie[/name_f], but you couldn’t go wrong with either one. They’re both great names.
I like [name_f]Callie[/name_f] best for a full name. I would prefer both of these names as nicknames for longer names (ex [name_f]Calista[/name_f] nn [name_f]Callie[/name_f], [name_f]Halona[/name_f] nn [name_f]Hallie[/name_f], etc), but [name_f]Callie[/name_f] is sweet.
I prefer [name_f]Callie[/name_f]. [name_f]Hallie[/name_f] doesn’t do anything for me.
I go by [name_u]Ali[/name_u] prn. [name_u]Allie[/name_u] which is pretty common where I live and it’s easier to be confused with [name_f]Hallie[/name_f]. [name_f]Callie[/name_f] has a more distinct sound and more feminine/pretty in my opinion
[name_f]Callie[/name_f] is much better. [name_f]Hallie[/name_f] got very over used for a while. Although many people spelled it different, like [name_u]Haley[/name_u] or [name_f]Hailey[/name_f].
I’ve actually struggled with the same question.I love both but I slightly adore [name_f]Hallie[/name_f] more. I know several little [name_f]Callie[/name_f]'s. Maybe it’s more popular in the south because since I’ve been in college in the north I haven’t heard it at all.