Return to app behavior after phone call different in native code than UIWebView - iphone

Question

According to Apple's documentation, in order to make phone call from my app, I need to implement the following protocols:
HTML link:
1-408-555-5555
Native application URL string:
tel:[phone]
However, upon completion of a phone call initiated from an HTML link inside a UIWebView, I am redirected right back to my application. But upon completion of a phone call made from a native application URL string, my iphone stays in the iphone's regular phone application, and if I want to return to my application I have to do so manually.
As far as I can tell from reading what others have said, there is no way to change this behavior.
Here is my question:
Is it true that it's impossible
to return to an application after
making a phone call from a native
application URL string?
Would there be any downside to
implementing a UIWebView instead of
a UILabel in situations where I
really wanted the user to be
redirected back to my application
after completing a phone call?

Answer 1

The simplest way seems to be:
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:#"telprompt:0123456789"]];
You will get a prompt and your app will regain focus after the call is finished.

Answer 2

Behavior does differ between calling -[UIApplication openURL:] with a tel: URL, and clicking a link to the same URL in a UIWebView.
Using a UIWebView instead of a UILabel might have some downsides, but you don't have to actually display the UIWebView to get its tel URL handling behavior. Instead, just load a tel URL request in an instance of UIWebView without adding it to your view hierarchy.
For example:
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#interface PhoneCaller : NSObject
{
#private
UIWebView *webview;
}
- (void)callTelURL:(NSURL *)url;
#end
#implementation
- (id)init
{
self = [super init];
if (self)
{
webview = [[UIWebView alloc] init];
}
return self;
}
- (void)callTelURL:(NSURL *)url
{
[webview loadRequest:[NSURLRequest requestWithURL:url]];
}
- (void)dealloc
{
[webview release];
[super dealloc];
}
#end

Answer 3

Allow me to simplify a bit. All you need is this little snippet:
UIWebView *callWebview = [[UIWebView alloc] init];
NSURL *telURL = [NSURL URLWithString:#"tel:number-to-call"];
[callWebview loadRequest:[NSURLRequest requestWithURL:telURL]];
which I got here.
*Recently tested successfully on iOS 5.0.

Answer 4

The Eric's Brotto method still works in 5.1. You have to add the webview to the main view before the loadRequest, like this:
NSString *cleanedString = [[phoneNumber componentsSeparatedByCharactersInSet:[[NSCharacterSet characterSetWithCharactersInString:#"0123456789-+()"] invertedSet]] componentsJoinedByString:#""];
NSString *escapedPhoneNumber = [cleanedString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *telURL = [NSURL URLWithString:[NSString stringWithFormat:#"tel://%#", escapedPhoneNumber]];
UIWebView *mCallWebview = [[UIWebView alloc] init] ;
[self.view addSubview:mCallWebview];
[mCallWebview loadRequest:[NSURLRequest requestWithURL:telURL]];
(I added a phone number cleaner, to delete any non-number char that blocks this method)