Just curious what apps you guys can't live without? For instance, when you are away from your computer and you get a hot lead that you need to research real quick. Or, any remodeling apps or CRM tools that help you manage the day-to-day on your phone.
Regarding checking comps specifically, I usually use Zillow if I need a quick snapshot of the neighborhood (no not the "Zestimate", but just to look at comps), but I think that's fubar with the most recent update. Check out these two screenshots, one with the desktop and one with the mobile app, exact same address, exact same filter criteria, very different results.
Here are some of the ones I use frequently which have a great user interface without unwanted ads, etc. and are all free:
Mortgage Calculator Plus - allows you to quickly look up mortgage costs (principal and interest) and from there, has a very handy feature on add in extra payments, taxes, insurance, etc. .. Another cool thing is the amortization schedule that is quickly found for each of the criteria entered. I used to use Bankrate.com but this app is so much quicker and easier
Loopnet - If searching for multi-family (or commercial in general) they have a great app which I find more useful than their website. And in terms of searching commercial properties, I've found them to be most comprehensive
Evernote - If you are doing a lot of transactions or have a lot of properties or are in the realtor business (or all of the above) Evernote is great because it'll allow you to load all this data like contracts, etc. and then you can quickly upload or reference them on the app. Very helpful when you're on the go and don't want to try and look stuff up all the time on your email inbox...
SamCard - did you just meet someone that you want to connect with and grab their business card? Just snap a photo of it through this app and its instantly entered as a contact on your phone. Not necessarily RE related but if your'e in RE, you're constantly looking to expand your network and save time, which this App helps in both instances
Personal Capital - This is an App that can basically take all your financial data and put it into a simple app that can calculate your net worth. Many know that calculating this number often is very helpful and motivating especially for aspiring RE investors. Well, this app makes this practice very quick and easy. Once the accounts are loaded, it quickly tabulates everything including things like your home's value, credit cards, car values, jewelry, loan amounts, bank accounts, 401ks, etc.
MileIQ - If you have rentals, are in sales or involved in RE as a business, you need to download this app to track your mileage. While the full version costs money, it's amazingly quick and easy and worth the annual fee! It also ensures you never forget to track your miles as some days we can forget to write this stuff down. Also makes it extremely easy at tax time to calculate
There are other apps I use as a Realtor (in addition to these above used for investing as well) but probably not worth mentioning to those not in that field
I use Everlance rather than MileIQ but it's the same type of app. Tracks your trips automatically and you can generate a report as often as you like.
Audible - Just for listening to books in the car.
IFTTT - If This Than That is cool so far. Still playing with it. @Brandon Turner mentioned it on a podcast and I have been trying it.
EVERNOTE - Everyone loves it.
WAZE - Been nav app ever.
MEETUP - Great for finding REI meetings.
ONE NOTE - I like One Note, some don't
ADOBESCAN - Lets you take a pic of something and make it a PDF for emailing/saving. Nice for taking a pic of a signiture page, invoice, etc.
aCalendar - I like aCalander a lot. It syncs with your google calendars, etc.
OFFERUP - Great for buying cheap stuff like appliances, etc. that are nearby.
And finally just a fun one - I like google sky map. Just plain fun.
My favorite App that also syncs to my desktop is OmniFocus. I use this to keep track of every project I have going on in life. Think of it as the reminders App on iOS on steroids.