Don's Home Technology Computing Mobile Devices Tablets & Smart Phones
Under Construction. 
See also Smart Phones in Telecom and Mobile Phones in products.
About:
  iOS (iPhone and iPad)

  Android
Products:
   Tablets
   Accessories
   iPhone
   Styluses
Apps:
App Store (iOS apps at Apple) | Play Store (Android at Google)
  iPad & iPhone
  Android
  Bible Apps
Notes/help/tips:
  Android
  Memory Requirements
  Data Usage
  Battery Life
Android and iOS (Apple) - Smart Phones and Tablets
July 2010 end of 2011 July 2013
Devices (million)
iOS 60 165
Android 20 130
Apps
iOS 225,000 500,000 900,000
Android 75,000 300,000 1,000,000

* More phones have android than iOS, but the iPad leads android tablets.

2014 Market Share

Apple's iOS tops Android to take first U.S. market share lead since 2012 | VentureBeat Feb. 2015

As of June 2014 800 million iOS devices and 900 million android devices had been sold.

See:
iOS 8 vs Android 5.0 Lollipop Review: Material Difference - Forbes

Comparison of Handset Market Industrialized World vs Emerging World in 2014
ITEM INDUSTRIALIZED WORLD EMERGING WORLD
Population 1.2 Billion 5.9 Billion
Mobile Subscriptions 2.1 Billion (175%) 5.2 Billion ( 88%)
Unique Subscribers 1.1 Billion ( 92%) 3.6 Billion ( 63%)
Handsets in use 1.7 Billion (142%) 4.0 Billion ( 67%)
Cameraphones 1.7 Billion (142%) 3.2 Billion ( 49%)
Smartphones 1.0 Billion ( 83%) 1.1 Billion ( 19%)
Source: TomiAhonen Phone Book 2014
Handset Market and Installed Base in 2014: The Total Handset Picture by Communities Dominate Blog
7-8 in tablets:
The advantage of these is that they are < 5 inches wide so will fit in most large jacket pockets and easier to hold in 1 hand.
Specs without 4G
Samsung galaxy
Tab PRO 8.4		 LG G Pad 8.3 Nexus 74 iPad Mini 3 Kindle Fire HDX 7
OS Android 4.4 Android 4.4 1 Android 51 iOS 8 Fire OS 4-based on
Android 4.4.2
Display 1600 x 2560 1200x1920 1200x1920768x1024 1200x1920
PPI 359 273 323 163
CPU 1.9GHz quad-core 1.7GHz quad-core 1.5GHz quad-core A7 1.3GHz dual-core Qualcomm Snapdragon
800 quad-core, 2.2 GHz
RAM 3GB 2GB 2GB 1GB 2GB
Storage 32 16 16 16 16/32/64
Expandable
memory		 microSD, microSDHC,
microSDXC up to 128 GB		 microSD, microSDHC,
microSDXC up to 64 GB		 None None None
Size (in) 8.38x4.94x0.26 8.54x4.98x0.33 7.9x4.5x0.34 7.9x5.3x0.28 7.32x5.04x0.35 in
Rear camera 8 MP 5 MP 5MP 5MP 1.3 MP
Camera Flash y n n n
GPS yes, GLONASS yes, GLONASS yes WiFi5 WiFi5
USB drive (OTG)6 y y 7
USB 2.0 2 2.0 2.0
Camcorder 30 fps 30 fps
Battery 4900 mAh 4600 mAh 3950 mAh 4440 mAh 4400 mAh
Bluetooth 4.0 4.0 4.0 4.0
Wi-Fi a, b, g, n, n 5GHz, ac a, b, g, n, n 5GHz a, b, g, n, n 5GHz a, b, g, n, n 5GHz 802.11 b/g/n
Price $350 $330 $229, 269 $249 $180, 229
NFC2 n n y n n
IR3 y n n n
Cons Rpts WiFi8 76 83 78
Cons Rpts
WiFi+ G4		 76 86 81
c|net 8.0 7.7 8.5 8.3 8.2
1. With OS upgrade available
2. NFC - Near Field Communication - Allows things like Google Wallet
3. IR - Infrared
See LG G Pad 8.3 vs Samsung Galaxy Tab S 8.4 - Phone specs comparison
4. The Nexus 7 (2013) has been replaced by the Nexus 6 ( $649) & 9 ( $399) [6.0" x 9.0" x 0.31"] [4128 x 3096]
I don't know why the 6 is more expensive. Maybe to get you to buy a 4G version at a discount with a data contract. See Nexus 9 Review & Rating | PCMag.com.

5. WiFi GPS - Determines location by WiFi signals detected.
The iPad mini and Kindle Fire with cellular have a regular GPS

6. USB drive On-The-Go (OTG) - A memory stick, camera, usb card reader, ... can be
7. Device needs to be jailbroken or rooted to connect an external usb drive or memory stick.
Nexus media importer will allow it on a Nexus 7

8. Best Tablet Buying Guide - Consumer Reports (CR) (requires account to see ratings) Dec 2014 

Other top rated 7-8" tablets (CR Tech - Electronics Buying Guide eBay)
                        Price  CR c|net
Sony Xperia Z3           $500  87  8.6
Samsung Galaxy Tab S 8.4 $400  87  8.3
iPad Mini 2              $430  85  8.8
Dell Venue 8 7000        $400  83  8.3
Lenovo Yoga Tablet 2 8   $250  79  7.0
NVIDIA Shield            $300  78
Google Nexus 9           $430  84  8.3
See Also:
May 2015 Consumer Reports review of 7-8" tablets
Samsung Galaxy Tab Pro 8.4 review: Comparisons | Tablets Review | TechRadar

Nexus 9 vs. iPad Air 2 - CNET Nov., 2014
Feature iPad Air 2 Nexus 9
Screen size 9.7 8.9
Resolution 2048x1536 2048x1536
OS iOS 8 Lollypop - 5.0
Design 4.3 3.0
User Interface 4.0 4.3
Features 4.7 4.7
Performance 4.7 4.3
Average 4.4 4.1
Another review - iPad Air 2 vs Nexus 9: Not Much of a Showdown - YouTube
  iPad wins - better build and more consistent.
Nexus more open.

Consumer Reports 2015 ratings of 140 tablets 

Misc:
  Damage & Repair
Links:
Mobile Device History
Voice and Text apps  for your laptop, tablet

iPhone 6 Plus compared to Galaxy Note 4, Nexus 6 and LG G3
Mobile Telephone Technologies
e-Books
eReaders
Location and Mapping with smart phones and tablets
Android leads US market share, iOS may have stopped growing, RIM is still falling -- Engadget Dec., 2011

Mobile Telephone Technologies


App Retention Improves - Apps Used Only Once Declines to 20%


See smart phones in products
last updated 8 Apr 2015