[Update 20100806: After a lot of criticism from you, the reader, and some suggestions of alternative apps, I have decided to change the rating for Calendars. I have not changed the original review - I am afraid if I changed that, the comments that follow might not make a lot of sense. However, at the end of the article I am adding a Response to Comments section]

The Overview

My iPhone provides me with nearly all my basic day to day needs and I actually use a lot of the built-in Apple apps to accomplish what I need to do: Mail for email, Notes for notes and ToDos, Maps for maps, Camera for photos, Safari for Web browsing, Calculator for…umm…calculating, Contacts, Phone, etc. You get the picture.

One app is noticeably absent from my list: Calendar. Why? I’m a Google user. Way back in the days of .mac and now .me, I refused to pay for an email account. Google was not only free but always seemed to have better features. I have built over four years of appointments, assignments, holidays, birthdays, journaling, etc in Google Calendar (even further with the stuff I back dated). I really don’t want to re-enter any of that.

“But, wait, Asshat” I hear you say, “you can sync up your Google Calendar and your iCal!” Sure. Check out: Sync using Google Sync or Sync Google using CalDAV. Not TOO complicated, is it? You don’t think so? Then you obviously aren’t an old school Mac user who likes Apple stuff because “It Just Works.™”

So why not just use the Google Mobile App and its calendar function? Because that is just a cheat – it simply links to calendar.google.com in Safari with your login credentials. Lame.

Calendars – well – “It Just Works.™” It connects to your Google Calendar – plus all sub calendars and calendars that others have shared with you. It syncs when it detects a connection or when you manually tell it to. It’s interface is easy to use – very clean and intuitive.

The Features

As I said, it syncs with ALL your Google calendars in a single account. You can also switch between accounts. I mean EASILY. Go to settings (within Calendars), Change Account, enter username and password. BAM! It loads a different Google Calendar. Simple. Easy. Elegant.

Calendars caches your data on your iPhone so you can use it offline. And it syncs any changes you make while offline very, very quickly. It is by far the smoothest calendar app I have used to date.

It displays all the standard views: month, week, day and list with the ability to jump back and forth through time or directly to the current day.

It has repeating events, adding attendees from your Contacts or by email address, a description, a location…pretty much any thing you can put into an event on Google Calendar you can add through Calendars. The only real limitation I found was that Calendars is not as flexible as Google Calendar is setting the frequency of a repeating event.

The Breakdown

The Good

It is Google Calendar on your iPhone. It does pretty much everything you can do through the web interface. Actually, it does it better than the web interface if you are accessing it through the Safari App.

The Bad

I really only found one bad thing – no landscape mode. Though this is not really a huge issue. The app does an incredible job of utilizing the screen space and I really only noticed the issue when I had an appointment with an INCREDIBLY long title.

The Verdict

Can’t you tell by all the gushing I did earlier in this article that I LOVE this app? If you are a Google Calendar user AT ALL, you should get this. Yeah, it may seem a bit pricey but quality apps are worth what you pay for them.

And Calendars is actually getting the highest praise from me that any app can get (BTW, Voodo got the same praise): I am KEEPING it on my iPhone even though I am done reviewing it. How’s that for a recommendation?

[Response to Comments:

First and foremost, Exchange/CalDAV/WebDAV/GSync/etc + Calendar.app is NOT an alternative to a full fledged app that is intended to interact with Google Calendar. Will it get your schedule and allow you to add appointments? Sure. Will it push notices? Yes. Does it have the power and flexibility of Calendars, CalenGoo, Saisuke, Pocket Informant or even the Google Calendar web app? No. Calendar.app is a base model car - these other apps are higher end models with options packages added in. So, please stop making the comment that Calendar.app is good enough - for people looking for this type of app, it's not....just like Camera.app plus Photoshop is not a substitute for Camera+ or Hipstamatic.

Second, I just mentioned CalenGoo, Saisuke, and Pocket Informant because YOU brought them to my attention. And I thank you all for opening my eyes.Appadvice.com has acquired all these apps and I will be reviewing them over the next month. You can make these suggestions in the comments of an article but that alerts us after the fact. At the very bottom of every page of our site is a link called "submit a tip." Use this to tell us about apps we should review, news we should know, or any other info about us, Apple, iDevices, etc. you want to share.

Third, Calendars is a Universal App - it works on both the iPhone/iPod touch and the iPad. I, as of this writing, use a 2G iPhone to do my reviews. I was not able to see how the app looked on an iPad. I am thinking about going to my local Apple Store and loading apps on the newest devices to play with them for a brief time to see if there are any major differences - but I cannot guarantee I'll always be able to do this. I will, however, try to remember to add a note about what device I am using for my reviews from now on.

Fourth, we use pretty much the same comments policy system as everyone else. That includes no Ad Hominem attacks. No name calling, basically. And I'd already called myself an Asshat in the article...isn't that good enough for everyone? ;)

/Response to Comments]