javascript - API calls in angularJS right after each other -

i have problem using angular in ionic mobile project , have piece of code working great in desktop environment. 3 api call web server 500ms after each other. in phone using lower connection 1 of call fails whole process fail. there way api calls in exact moment previous 1 finish? mean, not using fixed amount of time.

//get member information $timeout(function() {   membersservice.getmember(community.url, community.user.api_key, community.user.auth_token, $stateparams.userid).   success(function(data) {     $scope.member = data.result;   }); }, 500);  $timeout(function() {   messagesservice.getconversation(community.url, community.user.api_key, community.user.auth_token, community.user.user_info.guid, $stateparams.userid, "from").   success(function(data) {     if(data.result["entities"].length > 0)  {       messages = messages.concat(data.result["entities"]);       subject = "re: "+data.result["entities"][data.result["entities"].length-1].title;     }     $scope.messagedata.subject = subject;   }); }, 1000);  $timeout(function() {   messagesservice.getconversation(community.url, community.user.api_key, community.user.auth_token, community.user.user_info.guid, $stateparams.userid, "to").   success(function(data) {     log = [];     if(data.result["entities"].length > 0)  {       angular.foreach(data.result["entities"], function(v, k) {         v.owner_guid = $stateparams.userid;         log.push(v);       }, log);       messages = messages.concat(log);     }     var log = [];     var count = 0;     angular.foreach(messages, function(v, k) {       messages_reorder.push(v);     }, log);   }); }, 1500); 

this result of implementing nesting promise chains:

var loadmemberinfo = function( userid )  {   return membersservice     .getmember(community.url, community.user.api_key, community.user.auth_token, $stateparams.userid)     .then(function(data)      {       $scope.member = data.result;     }); }, getconversationfrom = function()  {   return messagesservice   .getconversation(community.url, community.user.api_key, community.user.auth_token, community.user.user_info.guid, $stateparams.userid, "from")   .then(function(cf) {     if(cf.data.result["entities"].length > 0)  {       messages = messages.concat(cf.data.result["entities"]);       subject = "re: "+cf.data.result["entities"][cf.data.result["entities"].length-1].title;     }     $scope.messagedata.subject = subject;   }); }, getconversationto = function()  {   messagesservice   .getconversation(community.url, community.user.api_key, community.user.auth_token, community.user.user_info.guid, $stateparams.userid, "to")   .then(function(ct) {     log = [];     if(ct.data.result["entities"].length > 0)  {       angular.foreach(ct.data.result["entities"], function(v, k) {         v.owner_guid = $stateparams.userid;         log.push(v);       }, log);       messages = messages.concat(log);     }     //order array     messages = messages.sort(function(a,b) { return a.time_created - b.time_created } );      var log = [];     var count = 0;      angular.foreach(messages, function(v, k) {       messages_reorder.push(v);     }, log);   }); }, orderfullconversation = function()  {   $ionicloading.hide();   console.log(messages);   if(messages_reorder.length > 5) {     var messages_partial = messages_reorder.slice(messages_reorder.length-5,messages_reorder.length);   }   else  {     var messages_partial = messages_reorder;   }   $scope.messages = messages_partial;   $scope.community = community; };   loadmemberinfo( $stateparams.userid )   .then( getconversationfrom )   .then( getconversationto )   .then( orderfullconversation ); 

more details here