Did I miss your favorite? Let me know in the comments!
Business Calendar 2 (Free. Pro: $4.99. Android only) Great selection of colors. Year, month, week, day task panes that have a cool slider. Five easy to use widgets to stay informed about your upcoming events. Syncs with Outlook and Google calendar. Heat map shows when you're busiest and when you might have free time to schedule something. Pro version gives weather, connects to your contacts, schedules missed calls automatically, light and dark themes, multiple fonts, and much more. I liked that you can customize the colors, assign each day of the week a different color, and do all kinds of cool customizations.
Play Store: https://play.google.com/store/apps/details?id=com.appgenix.bizcal&hl=en
Cal - Google / Calendar Exchange (Free. Android and iOS) Brought to you by Any.do the company responsible for a very popular task productivity app. This calendar has a very nice daily agenda. Suggests people in your contacts and social media you might invite to events. Integrated map for directions or to suggest a nearby place for your meeting. Attach notes to events. Big bright buttons, nice background images, easy to read landscape mode, beautiful at a month view, and a very slick interface that's easy to use. I found it to figure out certain tasks and impossible to add multiple calendars but I will say it is very readable with big fonts and bright colors.
Play Store: https://play.google.com/store/apps/details?id=com.anydo.cal&hl=en
App Store: https://itunes.apple.com/us/app/cal-shared-calendar-daily/id648287824?mt=8
Boxer Calendar (Free. Android only) Runner-up for a webby award for productivity. The app does day, month, year views. Users have 20 colors to choose from for events. Incorporates material design which means it is more intuitive and user friendly. Users can easily send their availability. Date picker makes navigation easier and the seven day agenda allows a nice chronological run-down of the week to come. Syncs with all calendar programs including Outlook and Google. Nice Boxer widget shows the days events at a glance. If users have the Boxer e-mail app it will find events and meeting in your e-mails to automatically add to your calendar. I found it very intuitive and easy to add multiple calendars.
Play Store: https://play.google.com/store/apps/details?id=com.boxer.calendar&hl=en
Sunrise (Free. iOS and Android) Currently owed by Microsoft this calendar app is the one that I use on my iPhone and I usually recommend. You can add multiple calendars easily, add widgets on both OS systems, invite event attendees, add location, set reminders, make notes, it will automatically add events from your e-mail, easily edit events, horizontal and vertical views, daily or monthly view, sync all types of calendars, and it has a clean intuitive interface.
App Store: https://itunes.apple.com/us/app/sunrise-calendar-outlook-app/id599114150?mt=8
Play Store: https://play.google.com/store/apps/details?id=am.sunrise.android.calendar&hl=en
