Cost: Free
This app summarizes non-fiction books so you can understand the key points without reading the books cover to cover.

Sorting app for news and information.
Keep up with the topic and trends you care about, without the overwhelm.
Feedly offers you the cure to information in three easy steps:

Cost: $9.99
Use your iPad as a second monitor with this app.

Note: Newer iPads should have this feature built in if you are using a Mac.

Cost: Free
Featured as an App Store Best.
MindNode makes mind mapping easy. Mind maps are a visual representation of your ideas, starting with a central thought and growing from there. This allows you to brainstorm & organize your thoughts in an intuitive way, so you can focus on the idea behind it.

Cost: Free
A simple app for creating flowcharts

Cost: Free
Mind maping tool to facilitate branstorming, idea collection and thought structuring

Cost:
$9.99
Timeline 3D for iOS 7 is a simple way to create beautiful multimedia timelines.

Free (but may require purchase of subscription)
Timeline Presenter lets you take data and events and turn them into simple and efficient timelines with incredible workflow capabilities. It’s the perfect tool to organize and collaborate on multiple paths of information within one project—from PDFs to videos to audio. Present simplified versions of intricate histories with interactive timelines.

It's so simple & convenient - just sketch & take notes about anything in your mind.
Save and share your novel ideas in the school, cafeteria, office or even on the bed.

Cost: Free
Bamboo Paper, a notebook app designed to give you the best and most realistic inking experience on your iPad or iPad mini. Do more with your ideas - sketch or write them in an authentic paper-like digital notebook.

Sign, send, and succeed with the world’s #1 eSignature solution. Create your electronic signature, collect signatures on documents, and send instant reminders, anywhere at anytime. Skip the printer or fax machine, and upload and sign documents that require your signature. Share a signed copy, view the complete audit trail, and store all your important documents in DocuSign.

Cost: Free
Dragon Dictation is an easy-to-use voice recognition application powered by Dragon® NaturallySpeaking® that allows you to easily speak and instantly see your text or email messages. In fact, it’s up to five (5) times faster than typing on the keyboard.

Editorial is a plain text editor for the iPad with powerful automation tools and a beautiful inline preview for writing Markdown.

You can combine a large selection of simple text processing actions into your very own workflows — all in an intuitive drag'n'drop interface that makes it easy to see what's happening.

Cost: Free
Evernote is an easy-to-use, free app that helps you remember everything across all of the devices you use. Stay organized, save your ideas and improve productivity. Evernote lets you take notes, capture photos, create to-do lists, record voice reminders--and makes these notes completely searchable, whether you are at home, at work, or on the go.

Based off the book Getting Things Done by David Allen, Get It Done lets you focus on what's important for today and keeps everything else out of your way.

Cost $4.99
Use GoodReader with Dropbox to sync with your iPad.
An app that I see recommended by lawyers for lawyers. Does just about anything you would want with PDF files, word documents, etc.

Cost: Free
Google's spreadsheet app

Document signing app by subscritpion

Well rated by users, note taking app

Cost: $7.99
Note taking app., lots of useful features, well rated by users.

Cost: $10, free with iPad Air and Ipad Mini Retina
Complete word processor app integrates with iCloud so docs sync on all devices

Take your to-do list anywhere with this feature-packed app; never forget the milk (or anything else) again. Remember The Milk (RTM) for iPhone, iPod touch and iPad connects with the popular online service of the same name. With millions of users worldwide, Remember The Milk is everywhere you are: from mobile to the web to apps including Outlook, iCal, Gmail, Google Calendar, Twitter, and more. Learn more at www.rememberthemilk.com

People are using Simplenote to keep notes, lists, ideas and more. Your notes automatically synchronize with your computer and all your devices. It's extremely easy to use. For those who want more power, you can also use tags, pins, versions, and sharing.

Cost: Free version & $4.99 for version that allows you to review & edit multiple documents
See full review at Lawsites, http://www.lawsitesblog.com/2017/03/app-may-forever-change-read-legal-documents.html

Price $9.99
Air Display 3 turns your iOS screen into a wireless (or USB!) display for your Mac. Increase your productivity with extra screen real estate or mirror your Mac computer display to your iOS device. (Windows users, stay tuned. For now, you want Air Display 2.)

With 10GB of free storage, Box makes it easy to store, manage and work with all your files and documents wherever you are - on the web, from your desktop and on your iPhone and iPad.

Box for iPhone and iPad helps you get work done on the go. It's fast, secure and simple to use, so you can be productive from anywhere. More than 20 million users and 200,000 companies use Box - including 97% of the Fortune 500.

Dropbox lets you bring all your photos, docs, and videos anywhere and share them easily. Access any file you save to your Dropbox from all your computers, iPhone, iPad and even the Dropbox website!

Features:
• Access all your photos, docs and videos from any device.
• 2 GB of space when you sign up -- free!
• Automatically save photos and videos to Dropbox and earn up to 3 GB additional free space.
• Share a link to even your biggest files— no more attachments!
• Add files to your "Favorites" for fast, offline viewing.

Google Drive is one safe place for all your stuff. Upload photos, videos, documents, and other files that are important to you, then access what you need wherever you go, on any device. Get going with up to 15GB of storage. Free.

Cost: Free, can upgrade for $4.99
Tracks when email you send is opened.

Cost: Free
A remote desktop application that allows lawyers access to their files on their desktop anywhere they can locate an Internet connection.

Cost: $6.99
Print direct to most WiFi/Wireless printers without additional software. Print to ALL printers and any document type via your Mac/PC. Print remotely over 3G/4G and in corporate/other networks where WiFi is not available. View, store & print email, large documents & PDFs, files, attachments, photos, contacts and web pages on your iPad

Cost: Free
Securely access your computers from your iOS device.

• On each of your computers, set up remote access using the Chrome Remote Desktop app from Chrome Web Store.
• On your iOS device, open the app and tap on any of your online computers to connect.

Cost: $9.99
Let's you mark up PDF files from your iPad and allows you to add sticky notes, freehand drawings, fill in forms, add signatures, highlight, underline and strike through as you search, read through and edit your PDF document.

Cost: Free
PDF Scanner

Cost: $ 4.99
Scan multi-page documents to PDF, save or share by email, Evernote, Dropbox, Google Docs with OCR, etc.

Cost: Free
Useful calculator

Cost: $2.99
Turn your iPhone or iPad into a portable scanner

Cost: $2.99
Optimized for iPhone 5 but can but compatible with iPad

Cost: Free
Create quick, elegant presentations and slideshows, display on device, upload to web or export to PPT or PDF

Cost: $9.99
Keynote is a great App for creating presentations.