I have not been able to access Salesforce1 on my iPhone or iPad has something changed?

Salesforce1 Overview of Device Installation

Knowledge Article Number: 000006494


Description
What are the basics of Salesforce1 enablement and device installation?


Resolution

What if my company uses Login IP Restrictions?

For organizations with login IP restrictions, an administrator must utilize the Connected App setting (Enforce IP Restrictions with Admin approved oauth policy on Connected App) See Connected Apps help. NOTE: Enforce IP Restrictions is default.


How do I configure Salesforce1 security and access for my organization?

System Admins can now access the Salesforce1 configuration page by clicking:

    Setup | Manage Apps | Connected Apps | Salesforce1 for Android / Salesforce1 for iOS

There you can enable or disable Salesforce1 for your organization, and specify the types of mobile devices that can use Salesforce1.  You can configure Salesforce.com to only allow access from Salesforce1 installed on iOS or Android device (iPhone/iPad) via control through Connected Apps. Salesforce1 displays an error message if a user tries to use Salesforce1 on a restricted device (IP) or in an organization that disabled the Salesforce1 iOS or Android Connected App OR admin disabled the Web-based permission .


What about Language support?
Salesforce1 works with almost all Salesforce-supported locales and the fully-supported and end user languages. Salesforce1 supports 25 languages. (The Salesforce Help includes a complete list of supported locales and languages.) Languages that are read right to left, including
** Arabic and Hebrew, aren’t supported in this release.

Please see:
https://help.salesforce.com/HTViewHelpDoc?id=faq_getstart_what_languages_does.htm&language=en_US

Salesforce1 includes multi-currency support, but advanced currency management isn’t available



How do users install the Salesforce1 app?

Salesforce1 is available at the following application marketplaces:

    iOS - AppStore
    BB - AppWorld (Not supported - tentative plans for Spring '14 via BB10 OS via web-based - Safe Harbor)
    Android - Google Play
    Windows 8 (Not supported - tentative plans for web-based in 2014 - Safe Harbor)


NOTE: The Salesforce1 app is a Hybrid app (Native/HTML5). It uses a combination of local software rendered via the Embedded Browser application on the smartphone devices. Salesforce1 require browser caching (per iOS - do not operate in Private Browsing mode) and cookies to be enabled for it to function/authenticate. Salesforce1 is also available as a 100% browser based app as well.


IMPORTANT DEVICE REQUIREMENTS:
iOS: Requires iOS 6.0 or later. Compatible with iPhone, iPad, and iPod touch. This app is optimized for iPhone 5.

Android: (these requirements in effect at least through Winter '14 release time frame) While Chatter Mobile v3.4 is compatible with Android OS v4.0+, the Salesforce1 app v5.0 (released Nov 18th) is available only for Android OS v4.2+. A user with Android OS v4.0 or v4.1 attempting to download the Salesforce1 app today, will get the Chatter Mobile v3.4