I have used the paper based Macquarie Dictionary (2nd Ed) for years, however the iOS version is iPhone only and very basic, however the developers have said that an upcoming upgrade will be a universal app. I decided not to test the Oxford, as it was expensive and although tempting, I already had the Australian version which appears to be identical in operation. Note that Collins and the Advanced English apps use the same MSDictViewer engine. Also most pay-for dictionaries often have a cheaper "essential"/"concise" version available. Do you really want to pay for a reduced number of words? Why are you buying a dictionary with some of the words missing?! How are you supposed to read Melville if the dictionary doesn't have "grapnel", "Tophet", "copestone" and so forth.
Words tested: Piccaninny, Load, Tweet, Muggle, Oberon
My paper based Macquarie Dictionary (2nd Ed) has "piccaninny" with three definitions: 1. a Negro or coloured child. 2. an Aboriginal child. 3. A small child. For some reason, piccaninny (also pickaninny) is now considered offensive. So my favourite breakfast dish at Pancake Manor has recently been renamed to "Picadilly Dawn". I was taken aback by the offensive categorisation, so investigating current dictionary definitions was included in this research. Sadly the tested apps came up short compared to the paper based Macquarie definitions. All dictionaries that had the term also noted the word was (possibly) offensive. I assume this is a U.S. issue where any word that contains even a hint of ethnicity is considered offensive. Sadly, even the MacQuarie app did not have definition (3).
I used the number of definitions for the word "Load" to sort the list. "Tweet" was examined for the definition of short message on the Twitter internet service; this is a new word officially added by Oxford ... but oddly not in the Australian Oxford Dictionary. "Muggle" was also used for similar reasons. Finally "Oberon" was examined to see if both the Shakespeare character as well as the satellite of Uranus was listed; the MacQuarie app had only a definition for a town called Oberon, no Shakespeare, no moon; the paper version included a second definition of the name of an Indian actor born in 1911.
The apps usually report number of words stored in the dictionary, but have different ways of measuring this metric which makes comparison invalid. I did include the reported number at the end of the notes section, but this should be seen as a rough guide only.
This blogger's choice
All of the listed dictionary apps fail at some level. Because of this, I would suggest acquiring a couple of the free dictionaries no matter what you end up getting. For a recommendation from the selection below I would suggest the offering from Dictionary.com and the free offering from Merriam-Webster, they have a paid version if you don't like the advertisements. I liked the Collins for content. The Australian Oxford kept having temporary freeze sessions, even after rebooting, reinstalling, but otherwise had good content. WordBook XL is for the scrabble/crossword fiend with it's handy solver function.
|iPad app name||Cost||Size||Advert||Include|
|Dictionary.com||free||50Meg||Yes||Yes||1 def, origin||39 defs||No||Yes||Yes|
|Output: Email, facebook, twitter||Notes: History, bookmarks, voice input, shake for a word, 2000K|
|Chambers Dictionary||$10||25Meg||Yes||Yes||No||36 defs||No||No||No astro|
|Output: none||Notes: Bookmarks, random word, 260K|
|Macquarie Complete Australian||$35||19Meg||Only||Yes||3 defs, origin||31 defs||No||No||No|
|Output: Copy enabled||Notes: iPhone app tested, upgrade expected, 210K|
|Collins English Dictionary Unabridged||$37||21Meg||Yes||Yes||2 defs, origin||28 defs||Yes||No||Yes|
|Output: none||Notes: Bookmarks, History, random word, cross references, 500K|
|Free Dictionary||free||1Meg||Yes||Yes||No||2 defs, origin||27 defs||No||Yes||Yes|
|Output: Copy enabled||Notes: Thesaurus, translation, download offline dictionary, bookmarks|
|Meriam-Webster||free||21Meg||Yes||Yes||1 def, origin||24 defs||No||No||No astro|
|Output: none||Notes: Voice search|
|Australian Oxford||$30||166Meg||Yes||Yes||2 defs, origin||18 defs||No||No||Yes|
|Output: none||Notes: History, bookmarks, 170K|
|Dictionary Free||Free||27Meg||Yes||Yes||1 def||14 defs||No||No||No|
|Output: Copy enabled||Notes: Link to wikipedia, bookmarks, history, 140K|
|Dictionary! for iPad||free||11Meg||Yes||Yes||1 def||14 defs||No||No||Yes|
|Output: none||Notes: Links to wiktionary, ugly, 200K|
|WordBook XL||$4||20Meg||Yes||1 def||14 defs||No||No||Yes|
|Output: Email||Notes: Bookmarks, Notes, Solver (word puzzles), 220K|
|WordWeb||free||29Meg||Yes||Yes||No||14 defs||Yes||Yes||No astro|
|Output: none||Notes: Bookmarks, random word, cross references, 285K|
|Advanced English Dictionary and Thesaurus||free||22Meg||Yes||Yes||No||12 defs||No||No||No|
|Output: none||Notes: Bookmark, random word, word of the day, 140K|
|Oxford English Dictionary||$37||203Meg||Yes|
|- not tested -||Notes: Similar to Australian Oxford.|